Wessel Wessels

Author Archives: Wessel Wessels

Lifelong weather enthusiast and researcher. Interested in all things weather-related, and how global climate and local weather interact. Owner of multiple home weather stations for almost two decades, but still learning and expanding his knowledge base every day. He is dedicated to sharing his expertise and knowledge to get more people involved and interested in both their local and global weather and how it interacts with climate on a worldwide scale. Love sharing my knowledge on home weather stations, how they work, and the many ways you can use them to your advantage. All in all, he is just a bit of weather nerd.

Freezing Rain vs Sleet: Understanding The Differences Between The Two

Freezing Rain Vs Sleet

They are both occurrences of water rapidly cooling down, but that is where much of the similarities between freezing rain and sleet end.

If you live in a region where temperatures frequently drop to below freezing point, you are probably already quite familiar with the terms "freezing rain" and "sleet."

Unfortunately, these two weather phenomena often get mentioned during weather forecasts and meteorological discussions, without a proper explanation of the meaning of each event. This can lead to confusion and make it hard to distinguish between the two.

The Difference Between Freezing Rain And Sleet

As will be illustrated throughout this article, there are several similarities, but also some clear differences between freezing rain and ice. Before delving into a more in-depth discussion, one first needs to establish the core differences between the two events are:

What Is The Difference Between Freezing Rain And Sleet?

The Difference Between Freezing Rain And Sleet

Freezing rain does not travel far enough through a layer of cold air to freeze, while sleet travels a longer distance through the freezing layer, which allows it to turn into solid ice.

As a result, freezing rain reaches the ground in liquid form and turns into ice on contact while sleet falls on the surface as solid pellets of ice.

Although both freezing rain and sleet fall through a layer of air with sub-zero temperatures, it is clear that they have very different characteristics, with each one also having a contrasting impact on their surroundings.

The most significant visual difference is that freezing rain falls on the ground in liquid form while sleet reaches the surface as ice pellets. A common misconception is that sleet as a form of ice will pose the most significant danger, but it is not that simple. 

The best way to understand the similarities and differences between these two meteorological phenomena is to take a closer look at each one.

Freezing Rain: What It Is And How It Forms

Although sleet has already been briefly defined earlier on, it is important to clearly and concisely state what it is before looking at how it forms:

What Is Freezing Rain

Freezing rain occurs when raindrops travel through a layer of freezing air too shallow to turn it into ice. Instead, it turns the precipitation into supercooled (cooled to below freezing) waterdrops, which instantly freeze when coming into contact with any object on the ground surface.

It is this last characteristic of freezing rain that makes it especially dangerous for humans, as will be explained in more detail shortly. The attributes of this phenomenon can largely be attributed to the way in which it forms.

How Freezing Rain Form

Freezing rain is often closely associated with the arrival of a warm front, which creates the ideal conditions for the formation of this occurrence. This is especially evident when this front moves into a region that already experiences subzero temperatures.

  1. 1
    Warm air aloft that accompanies a warm front, in combination with a layer of subfreezing air (air with temperatures below freezing) near the ground, forms the critical components for freezing rain.
  2. 2
    During cold winter months, precipitation often occurs as snow or other solid forms in regions experiencing freezing temperatures.
  3. 3
    As snow travels through the warm air, it melts and turns into raindrops.
  4. 4
    As it continues to fall, the raindrops encounter the subfreezing air near the ground, which cools it down rapidly. 
  5. 5
    However, the layer of cold air is too shallow to allow for the formation of ice, and the rain continues to the surface as supercooled waterdrops.
  6. 6
    As it reaches the ground, the raindrops instantly turn solid as it covers the surface it comes into contact with with a layer of ice.

It is this last step in the formation of freezing rain that makes it so dangerous to human activity in affected areas. As it comes into come into contact with a surface, freezing rain covers it with a layer of ice that is almost invisible to the naked eye.

The layer of ice is extremely slippery, which makes any movement over it very hazardous. On icy roads, it can lead to vehicles losing control and causing potentially fatal accidents. On sidewalks, pedestrians are at danger of slipping and serious injury. 

Sleet: What It Is And How It Forms

Before shifting the attention to the steps involved in the formation of sleet, the following summary will help to understand how sleet differs from freezing rain.

What Is Sleet

Sleet occurs when raindrops travel through a deep enough layer of freezing air to allow it to form ice. As a result, the frozen precipitation reaches the ground in the form of ice pellets.

Sleet follows the same process that is responsible for the formation of freezing rain, with one exception. The only notable difference between the formation of freezing rain and sleet is the depth of the layer of cold (subfreezing) air it has to travel through.

If the layer is too shallow, freezing rain occurs. A deeper layer, however, allows raindrops to travel further, leading to the formation of ice (sleet).

How Sleet Forms

The following steps will illustrate just how similar the process of forming sleet is to the one responsible for the creation of freezing rain:

  1. 1
    Warm air aloft that accompanies a warm front, in combination with a layer of subfreezing air (air with temperatures below freezing) near the ground, forms the critical components for freezing rain.
  2. 2
    During cold winter months, precipitation often occurs as snow or other solid forms in regions experiencing freezing temperatures.
  3. 3
    As snow travels through the warm air, it melts and turns into raindrops.
  4. 4
    As it continues to fall, the raindrops encounter the subfreezing air near the ground, which cools it down rapidly. 
  5. 5
    The layer of cold air is deep enough to allow the raindrops to travel further and freeze again. 
  6. 6
    As a result, the precipitation reaches the ground in the form of ice pellets, better known as sleet.

From these steps, it is clear to see how both freezing rain and sleet follow the exact same path up until point five. It is the depth of the layer of subfreezing air that allows raindrops to travel far enough to form ice pellets (sleet). 

Like freezing rain, sleet is responsible for creating dangerous conditions on roads, sidewalks, and other surfaces it accumulates. Fallen sleet is already quite hazardous, but as it starts to melt and mixes with snow, it becomes very slippery and potentially deadly.


Freezing rain and sleet are two weather phenomena that have several similarities, but also some core differences that set them apart. This post clearly highlighted these differences.

The article also illustrated how a simple variable, such as the depth of the layer of subfreezing air, completely change the characteristics of precipitation and result in two completely different weather occurrences.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  clicking on this link .

Until next time, keep your eye on the weather!


List Of The Most Dangerous Weather Conditions On Earth

What Is The Most Dangerous Type Of Weather

Several different weather events can lay claim to the title of "Deadliest Weather Phenomenon". We list the most dangerous weather conditions on Earth.

As the previous paragraph stated, several weather phenomena can be regarded as the deadliest or most dangerous. This raises the questions as to what the most dangerous weather phenomenon in the world is. The answer is not that straightforward.

Determining the most deadly weather phenomenon on the planet mostly depends on time and scale. And depending on which criteria gets used, the outcome may vary dramatically.

For example, some atmospheric occurrences (e.g., hurricanes) are hundreds of miles in diameter and last for several days. Others (e.g., tornadoes) are less than a mile wide with a lifespan fewer than 15 minutes.

As a result, there is more than one atmospheric condition that can claim the title of the deadliest weather phenomenon. This post demonstrates how it depends on the lens through which you view each occurrence and what factors you use to measure its impact.

The Most Deadly Weather Phenomenon

As the introduction eluded to, there is no clearcut answer as to which meteorological occurrence can be regarded as the deadliest or most dangerous. Each one has to be viewed in the context of time and scale.

With this said, the following weather phenomena are arguably the most deadly weather occurrences as defined by their size, duration, and severity:

What Is The Most Deadly Weather Phenomenon On Earth?

List Of The Most Dangerous Weather Conditions On Earth

In terms of immediate danger, destruction, and threat to lives, tornadoes are considered the most deadly weather phenomena.

In terms of total fatalities measured over time, drought and flooding are by far the most deadly and devastating.

Although it is accurate and concise, one needs to properly unpack this summary to gain a thorough understanding of how and why these weather occurrences have such an impact on the environment and human lives. 

As already mentioned, no one phenomenon can claim the title as the deadliest regardless of context. Depending on the scale, duration, and intensity of the occurrence, several weather conditions qualify as the most dangerous and destructive.

Dangerous weather conditions vary from occurrences a few feet to hundreds of miles in diameter and lasting from less than an hour to longer than a week. 

The following list provides a clear and detailed explanation of the deadliest weather phenomena on the planet and the circumstances under which they occur.

List Of The Most Dangerous Weather Conditions

The weather phenomena in the following list are not all independent weather systems. Some are part of a larger storm system, some are the direct or indirect result of another weather occurrence, while others are completely self-contained weather systems.

Although they do not appear in any definitive order of importance, the atmospheric conditions that are generally accepted to be the most dangerous and destructive, receive priority at the top of this list:

Deadly Weather Collage
  1. Tornadoes
  2. Tropical Cyclones (Hurricanes, Cyclones, Typhoons)
  3. Lightning
  4. Extreme Heat
  5.  Droughts And Flooding
  6. Hail

Each of these weather conditions proofs uniquely dangerous when we take a closer look at each phenomenon and view it within the context that they occur:

1) Tornadoes

They are not the biggest in size, nor the most longlasting, but tornadoes are by far the deadliest and most destructive weather phenomenon that occurs over a small area in a relatively short period.

Most Dangerous Weather Conditions On Earth

They are not independent storms and are usually produced by massive thunderstorms called supercells. (The latter is commonly found in the Great Plains of the United States where cold and warm air masses meet to develop these large-scale storm systems.)

The deadliest tornado in recent history occurred in Bangladesh in 1989 and resulted in approximately 1300 deaths.

What Makes A Tornado Dangerous

  1. 1
    A tornado can appear with very little or no warning, which leaves a very limited time to seek shelter. (The average tornado warning time is about 13 minutes.)
  2. 2
    Although it only lasts for approximately 10 minutes or less, the amount of energy released by a tornado during this period is unmatched by any other storm system.
  3. 3
    Wind, the primary force of this storm, can easily exceed 480 km/h (300 mph) in a tornado. This is powerful enough to flatten most structures in its path.

These factors combine to contribute to the devastation of structures and loss of life that occur over a short period of time. You can find more in-depth information about tornadoes in this article

2) Tropical Cyclones (Hurricanes, Cyclones, Typhoons)

Moving up in scale and duration, few things come close to the destructive power of a tropical cyclone. With an average size of 200 miles in diameter and lasting for approximately six days, hurricanes are by far the deadliest and most destructive force on this scale.

("Tropical Cyclone" is the umbrella term used to describe hurricanes, typhoons, and cyclones. These storms are basically identical, with the only difference being the location where they occur, as well as their direction of rotation.)

Hurricanes and typhoons start as a small tropical depression over the warm waters of the Tropics. Over time it grows into a tropical storm, which eventually turns into a hurricane or typhoon under the right conditions.

The deadliest hurricane in recent history is Hurricane Mitch, which resulted in 11 374 deaths in 1998. It occurred in Central America in the regions of Honduras and Nicaragua.

What Makes A Tropical Cyclone Dangerous

  1. 1
    The most dangerous aspect of a tropical cyclone is the large-scale flooding that occurs as a direct result of heavy downpours. It is the leading cause of fatalities during and after a hurricane.
  2. 2
    The strong winds that accompany the storm systems can reach sustained speeds of over 260 km/h (161 mph). This enables them to cause damage in the outer bands, but are especially destructive in the storm's eyewall. 
  3. 3
    The sheer size of a cyclone results in widespread damage over an extensive area. Large regions get subjected to constant heavy rains and strong winds, which often leads to individuals being trapped in place and unable to get out of harm's way.
  4. 4
    The "eye of the storm" is a unique feature of hurricanes that makes them especially dangerous. It is a deceptively calm, cloudless area in the center of the storm that creates a false sense of security and causes residents to leave their shelters.
  5. 5
    Damage and fatalities as a result of a hurricane sometimes only materialize days (in some cases weeks) after the actual storm already passed. For example, water from high-lying regions can take days to reach valleys and cause widespread flooding.

Tropical cyclones are complex storm systems that require a complete and separate article to grasp a better understanding of how it functions. You can find more in-depth information about tropical cyclones/hurricanes in this article

3) Lightning

They may not cause as many fatalities and damage as tornadoes and hurricanes, but lightning is uniquely dangerous. It's unpredictability, and the power with which they hit makes a lighting strike deadly to humans and animals.


It is hard to get a precise number, but lightning is responsible for roughly 24 000 annual fatalities worldwide. In the United States, a relatively "underwhelming" number of 51 yearly deaths get reported. 

These figures may create the impression that lightning is less deadly than it really is, which will be a wrong and very dangerous assumption.

The worst incidents of lightning damage & deaths are caused by secondary events. One of the deadliest lightning strikes in history occurred when a church in Brescia, Italy, was struck in 1769. It ignited 90 tonnes of gunpowder, killing 3 000 people and destroying half the city. 

What Makes Lightning Dangerous

  1. 1
    Lightning is essentially a massive electrical discharge, able to generate up to 100 million volts. As a result, even if a human or animal suffer an indirect lightning strike, it is still more than powerful enough to kill or cause severe injuries.
  2. 2
    Lightning bolds also reaches extremely high temperatures of up to 27 700° Celsius (50 000° Fahrenheit.) This can lead to serious burn injuries & fatalities but is also responsible for starting deadly fires in urban and rural areas.
  3. 3
    The unpredictability and speed with which a lightning strike occurs make it especially dangerous. Although thunderstorms are predicted with a fair amount of accuracy, an actual lightning strike occurs without warning within milliseconds.
  4. 4
    Lightning strikes are not confined to thunderstorms. They also form part hurricanes, occur during volcanic eruptions, and are even produced during large forest fires.

For lightning to occur, the right atmospheric conditions need to be in place, which justifies a more elaborate explanation that falls outside the scope of this article. You can find more in-depth information about lightning in this article

4) Extreme Heat

Surprisingly, one of the deadliest phenomena that go by almost entirely unnoticed right in front of our eyes is extreme heat. One of the reasons this silent killer occurs almost unnoticed is as a result of the time over which it occurs and the absence of warning signs.

"Heatwaves are responsible for more human deaths per year than any other weather event"

Extreme Heat

For example, the heatwave that struck Europe in 2003 resulted in around 70 000 deaths. In 2010, the Siberian Heatwave that lasted 44 days, caused 56 000 deaths in Russia. Finally, more than 600 people die each year in the United States alone due to heat-related illnesses.

Conditions are classified as a heatwave when unusually hot temperatures persist for two days or longer. These types of events are on the increase due to no small part in global warming. It is no surprise then that extreme heat and drought go hand-in-hand.

(Both are the result of extended periods of solar radiation, as well as the prolonged absence of cold and wet atmospheric conditions.) 

What Makes Extreme Heat Dangerous

  1. 1
    A heatwave doesn't occur suddenly, but build up over several days and can last for over a week. Its deadly impact slowly takes its toll on both human and animal health with fatal consequences.
  2. 2
    Extreme heat does not have an early warning system in place compared to those developed for dangerous weather occurrences like hurricanes, lightning, and tornadoes.
  3. 3
    The relative quiet and uneventfulness that accompanies a heatwave, combined with little awareness of the immediate danger, allow it to do most of its damage without much notice.
  4. 4
    As more people move to urban environments like cities and other metropolitan areas, the Urban Heat Island Effect contributes and exasperate the effect of an already rapidly-warming planet.

Extreme heat should not be viewed in isolation, as it is usually part of a more extensive system and closely linked to global climate trends. It usually takes the form of a heatwave, of which you can find more detailed information in this article.

5) Drought And Flooding

The leading cause of human fatalities, measured over an extended period and regardless of scale, is drought & flooding. Although neither are independent meteorological phenomena, they both occur as a result of the presence or absence of specific weather conditions.


For example, as a result of climate change, a rise in global temperatures combined with the extended absence of rainclouds are causing certain parts of the world to experience extreme droughts.

Similarly, the heavy rain that occurs during and after large storms like tropical cyclones and monsoons can lead to largescale & widespread flooding in valleys & other low-lying regions.

Of the two, drought is by the most deadly with food shortages causing entire countries and vast regions to experience severe famine. In 1922, China experienced the worst drought in recorded history, with a death toll of 3 million human lives. 

(This drought is closely followed in severity by the Bengal famine of 1943 which claimed 1.9 million lives in Bangladesh, as well as the twin droughts that struck India in 1965 and resulted in 1.5 million fatalities.)

Flooding is not as deadly as droughts in terms of total numbers, but are also responsible for a large number of deaths due to drowning and food shortages. China again fell victim in 1887 with the Yellow River Flood, resulting in an estimated 900 000 - 2 million deaths.  

What Makes Drought And Flooding Dangerous

  1. 1
    Since all life on the planet depends on water, drought affects everything. Famine, a direct consequence of drought, are one of the leading cause of death in developing countries. (Developed countries are not exempt from the effects of drought!)
  2. 2
    Flooding that occurs as a result of a hurricane, monsoon, or another large storm, do not necessarily take place at the same time or location as the original event. It can happen days later, at a much larger scale, and at a distant location.
  3. 3
    The strength of the volume of moving water during flooding is especially deadly. Not only does low water levels create a false sense of security, but its ability to weaken and destroy structures adds an additional layer of danger to human life.
  4. 4
    Drought also has a severe economic impact that can be more destructive than drowning or food shortage. Extended periods of drought can cripple entire economies and destroy the livelihood of people involved in the agriculture sector.

To illustrate the economic impact of drought mentioned in this last point, it is worth noting that in the United States alone, annual losses due to this phenomenon are approaching the 9 billion dollar mark. It is easy to see how this will result in serious financial hardship. 

6) Hail

Hail is not an independent weather system, but form part of thunderstorms where the updrafts in cumulonimbus clouds are responsible for the formation of hailstones. It is also a direct result of a thunderstorm, which makes it easier to calculate its immediate impact. 


As a result of its visually striking physical attributes and familiarity among the general public, the real danger that a hailstorm pose is generally slightly exaggerated. This does not mean that it poses no threat, but it is not as deadly as commonly perceived.

Exactly how deadly hail is, mostly depends on the size of hailstones. It can vary in size from as small as a pea to the size of a grapefruit. The bigger the size of the hailstone, the more deadly and destructive a hailstorm will be.

The average size of a hailstone varies from 2.5 - 4.4 cm (1 - 1.73 inches) in diameter. Once the size exceeds 2 cm (0.80 inches), it starts to cause notable damage. Hailstones the size of grapefruits (10 cm or 4 inches) are considered very dangerous and deadly.

However, it is important to note that hail the size of grapefruits or tennis balls occurs very rarely, and the vast majority of hailstorms are harmless.

The deadliest hailstorm in history occurred close to Moradabad, India. Hailstones reportedly reached the size of goose eggs (7 - 11 cm or 3 - 4.5 inches) and killed 246 people on 30 April 1988.

The largest hailstone ever documented was 20 cm (8 inches) in diameter. It fell in South Dakota, United States, in 2010. To put it in context, it was the size of a volleyball and just under 2 pounds in weight.

What Makes Hail Dangerous

  1. 1
    Apart from the size and frequency of hail, the speed with which hailstones fall can make them deadly. Wind speeds can increase the velocity of a hailstorm and turn otherwise harmless sized stones into lethal projectiles.
  2. 2
    The abruptness with which hailstones fall without any or little warning makes it hard to shelter in time. Although hail is associated with large thunderstorms, it is hard to pinpoint where and when it will take place.

Hailstorms are not independent weather phenomena but form part of large thunderstorm systems with strongly developed updrafts. You can learn more about hail in this article.


As this article clearly illustrated, there is no clear weather phenomenon that can be considered the most deadly. It all depends on the size, severity, and scale of the event.

For example, nothing can compare to the destructive power of a tornado on a relatively small scale and duration. Move up to several hundred miles in size and measured over days, the strength and danger of a large hurricane are unmatched.

This article highlighted the most deadly weather phenomena on the planet, as well as the circumstances under which they occur.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


Understanding Weather Symbols Used In Forecasts To Know What To Expect From Future Atmospheric Conditions

Understanding Weather Symbols heading

Most of us have seen the familiar weather symbols used on television and online meteorological forecasts, our mobile weather apps, and even in traditional media. Still, some of these symbols can often appear confusing and unclear.

And you know what? You are definitely not alone and have absolutely nothing to feel embarrassed about! In fact, a huge percentage of people regularly watching weather forecasts, are often confused by the different symbols and terminologies used by the various weather services. 

What Are Weather Symbols?

Weather symbols are graphical representations of a range of atmospheric conditions commonly used during meteorological forecasts to display current and predict future weather conditions. It is commonly used in conjunction with a synoptic weather map but can be displayed separately as well.

The goal of this article is to help you better understand the most widely used symbols in weather forecasts, as well as the information that normally accompanies them.  

To keep things as simple as possible, we will focus on the weather symbols, illustrations, and terminologies use specifically in weather forecasts. We focus on the symbols, elements, and graphs used in weather maps, which you find in this article.

Weather Forecasting Symbols

It only makes sense to start with the elements most widely associated with weather forecasts, which are off-course the weather symbols. Let's take a look at the most commonly used ones and what they mean.

As you will soon see, the same symbols can be displayed to describe different weather condition by various applications and services. This can be very confusing, so I attempt to the most important weather conditions associated with them.

Sunny Symbol

Sunny Conditions

The most well-known of all the weather symbols. This symbol, indicating sunny conditions and clear skies, is also pretty straightforward and rarely used in any other way than to display exactly these conditions.

Partly Cloudy Day Symbol

Partly Cloudy (Day)

The day will be mostly sunny with patches of cloud cover during the day. The cloud cover my grow larger or dissipate throughout the day, depending on future atmospheric conditions, or simply put, "the way the weather is headed in".

Partly Cloudy Night Symbol

Partly Cloudy (Night)

The night will be mostly clear with patches of cloud cover during the day. The cloud cover my grow larger or dissipate throughout the night, depending on future atmospheric conditions, or simply put, "the way the weather is headed in".

Cloudy Symbol


The day/night will be mostly overcast with no or very little clear skies visible. The light color of the symbol normally indicates that no rainfall is imminent (yet).

Overcast Symbol


An indication that heavy cloud cover is expected throughout the day/night. This dark symbol is often an indication that rainfall may be possible, but not expected.

Cloudy With Light Rain Symbol

Cloudy With Light Showers

This symbol normally indicates cloudy conditions with light showers scattered throughout the day. These conditions may continue to persist, dissipate, or grow into heavier rainfall later on. 

Cloudy With Showers Symbol

Cloudy With Showers

Slightly heavier and more persistent showers are associated with this symbol. Normally these conditions also last longer and can be expected to last the duration of the day, depending on the season and type of weather system.

Cloudy With Heavy Showers Symbol

Cloudy With Heavy Showers

As the symbol and description indicate, heavy persistent showers can be expected. As with normal showers, its duration will largely depend on the season and type of weather system. 

Attention should be paid to additional information, like storm and flood warnings, as these conditions can occur during very heavy downpours.   

Partly Cloudy With Light Rain Symbol

Partly Cloudy With Light Showers  / Cloudy With Light Showers (Day)

These are one of the first symbols that can be very confusing, hence the dual description. Usually, it means the weather will be partly sunny, with some cloud cover & light showers to be expected. 

Some weather services are now using this symbol to indicate cloudy conditions with light rain, and use the sun to show that the conditions occur during the day. (In this instance no distinction is made between cloudy and partly cloudy weather.)

The best advice to follow when you see this symbol is to read the short forecast summary that usually accompanies any weather symbol.

Partly Cloudy With Light Rain Night Symbol

Partly Cloudy With Light Showers / Cloudy With Light Showers (Night)

Another symbol with a confusing dual personality. Usually, it indicates a partly clear night sky, with some cloud cover & light showers to be expected. 

Some weather services are now using this symbol to indicate cloudy conditions with light rain, and use the moon to show that the conditions occur during the night. (In this instance no distinction is made between cloudy and partly cloudy weather.)

Follow the same advice that was given in the previous section when you see this symbol.

Partly Cloudy With Rain Night Symbol

Partly Cloudy With Showers / Cloudy With Showers (Day)

And yet another symbol with a confusing dual personality. Usually, it means the weather will be partly sunny, with some cloud cover & showers to be expected. 

Some weather services are now using this symbol to indicate cloudy conditions with rain, and use the sun to show that the conditions occur during the day. (In this instance no distinction is made between cloudy and partly cloudy weather.)

Follow the same advice that was given in the previous section when you see this symbol.

Partly Cloudy With Rain Night Symbol

Partly Cloudy With Showers / Cloudy With Showers (Night)

Another symbol with a confusing dual personality. Usually, it indicates a partly clear night sky, with some cloud cover & showers to be expected.

Some weather services are now using this symbol to indicate cloudy conditions with rain, and use the moon to show that the conditions occur during the night. (In this instance no distinction is made between cloudy and partly cloudy weather.)

Follow the same advice that was given in the previous section when you see this symbol.

thunderstorm Symbol


Thunderstorms with strong winds, lightning, and heavy rain can be expected. These are one of the symbols that you should not ignore, simply due to the dangerous conditions that accompany a weather event. 

hail storm Symbol

Hail Storm

This symbol indicates a hail (water in its frozen form) storm. Hail is very often associated with thunderstorms due to the similar weather conditions that produce both. If you are interested, you can read more about hail in this article.

light snow fall Symbol

Light Snow Shower

A light shower of snow (a cluster of ice crystals) is expected to fall. In areas familiar with regular snowfall, this won't cause any concern.

If it takes place in a region that very seldom experience any snowfall, care should be taken to account for conditions that normally accompany snowfall, including a sudden drop in temperature and slippery conditions.

heavy snow fall Symbol

Heavy Snow Shower

A heavy shower of snow (a cluster of ice crystals) is expected to fall. Regardless of the location of familiarity, care should be taken to account for the potentially dangerous conditions that accompany heavy snowfall.

mist Symbol


Mist is nothing more than a high concentration of micro water droplets in the air near the surface of the ground. When mist is forecasted, this usually indicates damp conditions with variable degrees of low visibility. You should take this into account, especially when you plan on traveling. 

drizzle Symbol


When a drizzle is predicted, it usually means a very fine form of rain will occur. The water droplets can be very small, almost unnoticeable. It should not be ignored, however, as it is often very persistent, and can thoroughly drench you over time. 

sleet symbol


When sleet is forecasted, it usually means a combination of rain and snow, and even small ice pellets are expected to fall.

The formation of sleet is a little more complex than you may think. For a complete explanation, you can read more its formation and characteristics in this article. (Simply search for "sleet" in the text.)  

tropical storm symbol

Tropical Storm

This symbol, predicting a tropical storm is not often used in a weather forecast. When you do see it, however, you better sit up and pay serious attention. A tropical storm is destructive enough on its own. (You can find in-depth information about tropical storms, hurricanes, and cyclones in this article.)

However, a tropical storm can quickly turn into a hurricane. I don't think I need to tell you just how devastatingly powerful and destructive a hurricane can be. If you are unsure, read the article I mentioned in the previous paragraph.

Please Note 

All the weather forecasting symbols used in this post are just examples of what each symbol means in principle. 

Every weather service and application have their own version of each weather symbol which may look very different from the ones you have seen here. Some may be more elaborate and artistic with almost a photo-realistic look. Others may be extremely simplistic and in monochromatic color.

Some services and applications use symbols that have two drops or snowflakes to indicate light rain or snow, and multiple ones to indicate more severe versions of an event.

The point is, every service and application is different. Use the accompanying descriptions and your own discretion to interpret each symbol correctly.

The symbols used in this article should serve as a basic and accurate guideline to help you get a good overall understanding of the general meaning of the different weather forecasting icons and the weather conditions they represent.

The weather forecasting symbols used in this article, are an accurate reflection of the most commonly used icons in forecasting. 

A few minor symbols may be missing and, as already stated, there is a broad interpretation of these icons by different weather services and applications. 

Despite this fact, you are now much better equipped to correctly interpret and understand all the different shapes and sizes these symbols come in. 

Additional Forecast Information & Descriptions

The weather forecasting icons are the backbone of any weather forecast and help to quickly summarize future atmospheric conditions.

Often though, they are accompanied by additional information and a short text summary of the forecast to give you a better understanding of upcoming weather conditions.

Weather Forecast Example

Simple Example Of Weather Forecast With Additional Information

The forecast example above is just one of countless variations in the way weather predictions are displayed. I chose this specific one as it contains some of the most important supporting information needed to help you best understand how the weather will behave.

temperature symbol

Minimum/Maximum Temperature

Apart from the weather symbol itself, the maximum/minimum temperature is probably the best indicator of what future weather conditions will be like. It is also the part of the weather report most people pay attention to, as most of us would like to know how to dress and plan our day.

Therefore, temperature is clearly a vital part of getting an overall picture of the predicted atmospheric conditions. It normally measured in degrees Fahrenheit or Celsius (depending on your country's system of measurement).

To find out more about temperature, how it is measured, and its influence on the weather, you can find all this information in this article.

rainfall symbol

Likelihood Of Precipitation In Percentages

Almost as important as the temperature, is the predicted likelihood of rainfall. Who of us does not want to know whether it is going to rain and what the chances of actual rainfall are?

Like temperature, your country's system of measurement will determine whether rainfall is measured in inches or millimeters.  

wind speed symbol

Wind Speed And Direction

Wind speed and direction indicators are not that widely used, especially by weather services aimed at providing forecasts for the general public.

It is no less important though, and an important measurement for both weather enthusiasts and professional meteorologists. 

text description symbol

Short Text Summary

An often overlooked but very valuable part of a compact weather forecast, is the text summary. You may understand some (or even all) of the symbols and additional information supplied with the weather symbol/icon. 

An accurate text summary, however, rounds off the forecast by putting all the information into words to make sure everything is correctly understood.

iPhone Weather Symbols And Their Meaning

Just like all other smartphones and tablets, the popular iPhone and iPad also make use of weather symbols and icons to display weather information.

Although their icons may look slightly different than other devices, they serve the same purpose, and one won't have any difficulty understanding the meaning of each symbol.

The following list showcases some of the most common iPhone weather icons: 

iphone weather symbols

The illustration above shows some of the commonly used iPhone weather symbols and icons. Click on the image for a larger view.


If all the symbols and information displayed in a weather forecast didn't make sense to you before, you should now have a much clearer picture of what all the different elements mean and how to interpret them.

The primary goal of this article was to make sure you get a better understanding of the different weather forecasting symbols and elements to help you be better prepared for upcoming weather conditions.

The focus in this post was more on forecasting, and all elements associated with it. For this reason, I didn't pay much attention to the details of an actual weather map. I am addressing all the features, symbols and lines found in a weather map, in this article.

Feel free to leave me any comments, questions or suggestions, and I will get back to you as soon as possible.

Remember to join my  Mailing List  to be informed whenever a new article is released, and share new developments and helpful hints & tips.

Until next time, keep your eye on the weather!


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Does The Moon Affect The Weather? How Earth’s Only Satellite Is Influencing Our Atmosphere Conditions

Does The Moon Affect The Weather

Sitting approximately 380 000 km (236 000 miles) away from Earth, it's hard to imagine that the moon can have any influence on the planet's climate and weather.

One can easily assume that a "piece of rock" this far away from Earth, and a quarter of its size will have very little if any influence on the planet's atmospheric conditions. But you know what they say about assumptions...

In short, the moon does impact the planet's weather, but not in the way you may think.

This article explains how and why the moon impacts the weather and examines the mechanisms involved in the process.

Does The Moon Affect The Weather?

Clearly, a much broader explanation is needed to fully understand exactly how the moon impacts the planet's atmospheric conditions. But first, we need a more concise and precise answer to the primary question this post is addressing.

Does The Moon Affect The Weather?

How The Moon Affects The Weather

The moon does affect the weather, but indirectly. Through its gravitational force, it mainly has a direct effect on the ocean's tidal activity, which impacts the flow of the ocean currents in return.

And it is the flow of cold and warm ocean currents that largely determines weather conditions in most parts of the world.

From this cryptic description, it is evident that the moon's gravity, its tidal activity, and the ocean currents are the key components involved in the manipulation of weather activity in the atmosphere. The upcoming section will lay out exactly how this process takes place.

The primary way in which the moon affects the weather is through the indirect manipulation of ocean currents. The type of weather introduced to a new region, as a result, will largely depend on the properties of the ocean water present in the affected current.

(Warm water will favor cloud formation and is almost synonymous with tropical Cyclone development. Cold water, on the other hand, is more conducive to the creation of dry weather conditions.)

A second notable effect of the moon on atmospheric conditions is its impact on polar temperatures. Measurements taken by satellite showed that temperatures at the Poles are higher during Full Moon than New Moon.

On average, temperatures during Full Moon are 0.55° Celsius (0.99° Fahrenheit) higher than New Moon. These temperatures may seem small and insignificant, but even at this scale, it still has a significant effect on weather.

A less significant effect of the moon is its ability to increase air pressure at the edge of a tidal bulge, as the increased water height causes the air to compress slightly. In this case, the increase in atmospheric pressure is not large enough to have any impact on the weather.

How The Moon Affects The Weather

This section describes how the moon affects the weather on our planet. To understand the steps involved in this process, one needs to clarify two of the key components:

  1. Gravity  
  2. Ocean Tides

As already stated, gravity is one of the primary factors allowing the moon to influence weather and climate. In fact, it is ONLY the moon's gravitational force that enables it to have any impact on the Earth's atmospheric conditions.

As a result, it is essential to understand how gravity works and how it allows the moon and other celestial bodies with mass to exert force on different objects.

1) Gravitational Force Of The Moon On Earth

Gravity is the strength with which the planets and other large celestial bodies attract objects to their centers. All objects with mass also have gravity. And it is the large mass of the moon that enables it to display the strong gravitational force that even influences objects on Earth.

Gravitational Force Of The Moon On Earth

Diagram showing the impact of the moon on Earth's oceans, showing the tidal bulge that forms during High Tide.

The moon's gravity primarily influences the ocean tides on the planet's surface, which impacts the ocean currents and the weather in return.

(The moon's gravity influences all bodies of water, even the fluid in a cup of tea. The only reason the latter is not visible is that it occurs on such a small scale that it is visibly unnoticeable.)

And this brings us to the subject of ocean tides, the big disruptor that impacts ocean currents and helps to shape the weather:

2) How The Ocean Tides Affect The Weather

Tidal activity refers to the rise and fall (height) of water levels in a body of water like the ocean. The part of the sea directly underneath the moon's location experiences the largest "pull," causing water levels to expand vertically and rise. This rise is called a tidal bulge.

As the moon orbits the Earth, the tidal bulge follows it along the surface of the ocean. This horizontal movement is responsible for the creation of tides. And it is the creation of tides near the coast that largely impacts the flow and direction of ocean currents.

As previously mentioned, ocean currents are one of the primary drivers of weather activity. Their flow is mainly determined by three factors:

  1. Tidal Activity
  2. Wind Movement
  3. Thermohaline Circulation (A change in water density as a result of temperature and salinity.)

Ocean currents that are formed by tidal activity are known as tidal currents. Depending on the characteristics of the water present, these currents can result in rainy weather (in the presence of warm ocean water) or dry weather (mostly as a result of cold water).

Full Moon

During full moon, the moon's gravity is at its strongest, resulting in Spring Tide, where water levels are at its highest and sea levels at the coast rise more than at any other point. During this period, atmospheric readings are now also able to clearly show an increase in rainfall.

The moon does not influence the weather directly, but the thorough explanation in this segment of the different objects and occurrences involved makes it easier to understand. 

The complete process through which the moon impacts the weather on Earth can be summarized in the following steps:

  1. 1
    All objects have gravity, which increases with mass. The large mass of the moon allows it to exert more gravitational force on Earth than any other celestial body.
  2. 2
    The part of the ocean directly below the moon's position above the planet experience the biggest gravitational pull.
  3. 3
    Similar to a magnet attracting another metal object, the moon pulls at the surface of the ocean, causing it to expand vertically and increase in height. 
  4. 4
    This vertical expansion is known as a tidal bulge, which sweeps across the ocean's surface as it follows the moon orbit around the Earth.
  5. 5
    The tidal bulge is responsible for creating new and manipulating/redirecting existing ocean currents. Ocean currents affected by tides are called tidal currents.
  6. 6
    Ocean currents are one of the main driving forces of weather. As a result, the influence of tidal activity on these currents leads to the creation of new weather patterns, which depend on the characteristics of the water the currents carry.

In summary, this section explained how the moon affects the weather indirectly through gravity, which leads to the creation of ocean tides. In turn, tidal activity drives & shapes the ocean currents that are largely responsible for the formation of specific weather conditions. 


As this article clearly illustrated, the moon does affect the weather, but not directly. Through gravity, it is responsible for the creation of tides in the ocean directly below. In return, the tides influence ocean currents, which directly drive weather activity around the world.

The moon's impact on atmospheric conditions can seem insignificant. It does, however, have a big enough and noteworthy influence not to be ignored when gathering meteorological data or making a weather prediction. 

The primary aim of this post was to describe the effect of the moon on the Earth's weather, how it occurs, and also look at the different factors and processes involved. 

Feel free to leave me any comments, questions or suggestions, and I will get back to you as soon as possible.

Remember to join my Mailing List to be informed whenever a new article is released, and also receive helpful tips & information by simply  clicking on this link .

Until next time, keep your eye on the weather!


Arcus Clouds: What They Are And How They Form

Arcus Clouds - What They Are And How They Form

Clouds literally come in all shapes and sizes, but there is something unique about the appearance of arcus clouds. And they have more meaning than simply putting on a spectacular display.

Under the right conditions, many cloud formations make for some of the most striking photographs you can take. Some clouds, though, are so visually impressive and awe-inspiring that a picture doesn't do it justice. Arcus clouds are one such example.

This article focus on what arcus clouds are, how they form, as well as the different types of arcus clouds.

Arcus Cloud Definition

It is clear that arcus cloud formations are responsible for some of the most spectacular views one can observe from the planet's surface. But there is more substance to this meteorological phenomenon than merely looks.

What Is An Arcus Cloud?

what is an arcus cloud

"Arcus Cloud" is the umbrella term used for low-lying clouds that spreads out horizontally, usually from the boundary of a larger storm system like a thunderstorm.

These visually striking cloud formations usually appear in the form of shelf clouds or roll clouds.

The summary provides a concise but cryptic definition of what an arcus cloud is and how it forms. A broader definition is needed to fully understand this type of cloud formation.

Arcus clouds are low-altitude clouds with the cloud base forming at the height of approximately 2 kilometers (6500 feet).

Arcus clouds are divided into two main categories: Shelf Clouds and Roll Clouds. As a result, arcus clouds are either wedge-shaped or in the shape of a horizontal tube-shaped column (depending on whether a shelf or roll cloud develops).

The two major types of clouds associated with the formation of arcus clouds are Cumulus and Cumulonimbus. Notably, the severe updrafts and downdrafts present in cumulonimbus clouds are responsible for the creation of many spectacular arcus formations.

Unlike the cumulonimbus clouds that form the basis for the formation of many arcus clouds, arcus clouds themselves develop and spread out in a horizontal fashion.

Arcus clouds pose no direct danger in the form of precipitation or strong winds, but in many cases, act as a precursor for approaching thunderstorms and severe weather.

How Do Arcus Clouds Form?

Although the two types of arcus clouds, shelf and roll clouds, have unique characteristics and a specific way in which each one develops, they both have a similar origin.

Arcus Cloud Formation

Cold air flow out from the storm front and spreads horizontally, forcing the warmer air at the surface into the air. The arcus cloud forms along this border of rising warm air and advancing cold air.

The principle way in which arcus clouds form can be summarized in the following steps:

  1. 1
    Thunderstorms are characterized by strong updrafts and downdrafts in the stormcloud. It is the strong downdrafts present at the leading edge of a thundercloud that is primarily responsible for the creation of arcus clouds.
  2. 2
    Cold air, cooled down by altitude and precipitation, is carried to the ground by downdrafts from where it spreads out horizontally in front of the storm system. 
  3. 3
    The heavier cool air spreads out quickly over the ground and pushes underneath the warmer moist air, lifting it into the atmosphere.
  4. 4
    As the warm air rises and cools down, condensation takes place, which leads to the formation of arcus clouds with their unique shape & characteristics.
  5. 5
    Depending on the specific atmospheric conditions and location, this process leads to the formation of the familiar wedge-shaped shelf clouds, or the round cylindrical-shaped roll clouds.

Both shelf clouds and roll clouds each have a unique appearance with characteristics of their own, which we will address in the following section. 

Types Of Arcus Clouds

As stated in the summary, arcus clouds can be divided into two primary types of formations: 

  • Shelf Clouds
  • Roll Clouds.

These two types of arcus clouds may have a similar origin, but appear substantially different with different characteristics which can be best understood by looking at each cloud formation individually. 

Shelf Cloud: The Best-Known Arcus Cloud Formation

The most common type of arcus cloud is the ominous-looking shelf cloud that usually precedes large thunderstorms. When discussing arcus clouds, this is the type of cloud formation that generally springs to mind. 

What Is A Shelf Cloud?

what is a shelf cloud

A shelf cloud is a type of arcus cloud that is characterized by its wedge shape and horizontal development, which usually forms at low altitudes at the leading edge of storm clouds.

Shelf clouds usually develop out of the parent cloud called a cumulus congestus cloud. Congestus clouds are cumulus clouds which are taller than they are wide, in other words, with strong vertical development. They are also often a precursor to cumulonimbus clouds.

The familiar ragged-looking underside of a shelf cloud is a result of turbulent winds, as well as wind shear caused between the updrafts and downdrafts.

Arcus clouds in the shape of shelf clouds are synonymous with a derecho, a widespread and potentially devastating storm system you can read all about in this article

Shelf clouds appear at the leading edge of this dangerous storm front, and although they pose no danger themselves, their appearance point to the looming threat of the derecho that follows close in its footsteps.

As a shelf cloud passes overhead, it is usually followed by a dark tumultuous section of sky, commonly known as the whale's mouth in meteorological circles. This stretch of weather slots in between the appearance of shelf clouds and the arrival of the thunderstorm.

(The dark, turbulent stretch between the edge of a shelf cloud and a thunderstorm is sometimes characterized by a distinct wavy appearance, known as asperitas clouds. These clouds don't appear that often but are almost as spectacular as the shelf cloud itself.)

Shelf Cloud Formation

The formation of a shelf cloud is identical to the process described earlier in this post. From the fifth point, though, the process is unique to the development of shelf clouds:

As the cold air from the outflow boundary (leading edge of the storm) moves forward, it tilts the rising warm air along its boundary.

It is along this boundary between the warm updrafts and cold downdrafts that shelf clouds form. As the warm air keeps rising along this border, it cools down, and condensation takes place, which results in the formation of a shelf cloud.

Roll Cloud: Shelf Clouds' Less Famous Cousin

A lesser-known type of arcus formation is called a rolling cloud. It is the second of the two types of arcus clouds.

Although a roll cloud is classified as an arcus cloud, it differs significantly from its more famous cousin, the shelf cloud. One needs to take a closer look to understand its unique characteristics, but one first needs to define it more clearly: 

What Is A Roll Cloud?

what is a roll cloud

A roll cloud is a rare type of arcus cloud that is characterized by its round tube-shaped formation, which forms at very low altitudes and appears to rotate on its horizontal axis.

It acts as a single wave known as a soliton and, unlike a shelf cloud, develop completely independent from other clouds.

As already stated, the appearance of roll clouds is a rare occurrence. It is no less spectacular than well-documented cloud systems but is a relatively rare occurrence. The biggest reason for their scarcity, is that the weather conditions has to be close to perfect for them to occur.

In the WMO's Cloud Atlas, it is now officially called volutus clouds. Although it is still viewed as a type of arcus cloud, the World Meteorological Organization (WMO) recently classified it as an entirely separate cloud species.

What makes a roll cloud unique is that it appears as a solitary independent cloud, completely detached from any parent cloud. On very rare occasions, one can view several roll clouds appearing in succession.

Roll clouds also act like a soliton when it comes to its motion. A soliton is a single wave with a single crest that moves ahead without changing its speed or size. (Which sums up the movement of a roll cloud.)

It is evident that roll clouds have some characteristics that clearly distinguish it from shelf clouds, even though it still falls within the same family of clouds. 

Difference Between A Shelf Cloud And Roll Cloud

The biggest difference between a shelf cloud and a roll cloud is the fact that a shelf cloud forms part of the larger storm cloud from which leading-edge it develops, while a roll cloud is an entirely independent cloud, detached from any cloud formation.

The well-known Morning Glory Cloud formation is arguably the best example of a roll cloud formation. It is the only type of roll cloud that can be predicted with any amount of certainty, and occur mainly in Northern Australia and The Gulf OF Carpentaria.

Roll Cloud Formation

Although the formation of a roll cloud generally forms in the same way as the process described earlier in this post, it also differs in a significant way: 

A roll cloud forms completely independent from any bigger cloud system. In many cases, it occurs without any other significant cloud development even in sight. 

Although not physically attached to a parent cloud, a roll cloud still forms at the leading edge or gust front of a storm system.

In some instances, the downdrafts that accompany a storm system forms some distance in front of the stormcloud's edge. As a result, a roll cloud can form at the border between updrafts and downdrafts, without the presence of the larger storm cloud formation.

Sometimes, though, a thunderstorm will clear up and dissipate completely, leaving only the updrafts and downdrafts behind. In turn, they can lead to the formation of roll clouds in otherwise clear and fair weather.


It is clear that all arcus clouds follow a similar pattern when it comes to their development and factors involved in the process. The physical manifestation of the two types of arcus clouds, however, are dramatically different.

Shelf clouds develop their familiar ragged wedge-shaped form, while roll clouds are characterized by their round, tube-shaped formation. Shelf clouds further develop at the leading edge of a storm cloud, while roll clouds form independently from any other cloud.

In conclusion, this article focused on explaining what an arcus cloud is, how it develops, and highlighting the different types of arcus clouds. 

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


The Fogbow: Rainbow’s Less Glamorous Cousin

Fogbow: Rainbow's Less Glamorous Cousin

Whenever you see a fogbow, you will be forgiven for thinking you are observing a form of rainbow. Though you won't be completely wrong, fogbows are the result of a different meteorological occurrence.

Although they are both the result of the same meteorological process, a fogbow appears during foggy/misty conditions while a rainbow occurs in the presence of a rain shower (as the names suggest).

It may not seem like much of a difference, but the characteristics of fog results in a ghostly white phenomenon not too dissimilar from a rainbow stripped of all its color.

This article examines what a fogbow is, look at its characteristics, as well as how it occurs. 

Fogbow Definition

As the introduction already eluded to, in the simplest terms, a fogbow appears as a completely desaturated rainbow with its predominantly white appearance. 

Before delving deeper into why and how it occurs, one first needs a clear and precise definition of what a fogbow is.

What Is A Fogbow?

What Is A Fogbow

A fogbow is a predominantly white semicircular bow that appears in the presence of fog when sunlight is reflected by water droplets within the fog bank.

Unlike the luminous spectral colors of a rainbow, a fogbow appears primarily white as a result of the way in which the microdroplets in fog reflects sunlight.

This summary provides a concise explanation of a fogbow, but to better understand why it occurs and how it differs from its more glamorous cousin, the rainbow, a broader clarification is needed. 

Although the name "fogbow" is the most commonly known and widely used name for this phenomenon, a few other terms are also synonymous with this occurrence:

  1. White Rainbow (Aptly named after its predominantly white appearance.) 
  2. Circle Of Ulloa (Named after General Antonio de Ulloa, who first draw attention to the phenomenon in the 18th century.)
  3. Ulloa's Ring (Another variation of the name used in the previous point.)
  4. Ghost Rainbow (Named after the ghostly white appearance of a fogbow.)

A fogbow is a relatively rare sight compared to rainbows, and do not occur that often. What makes them even harder to spot, is the fact that they can appear almost indistinguishable from the surrounding fog with only a hint of contrast that makes visible.

white rainbow

Since a fogbow appears at the antisolar point, the sun needs to be approximately 20 degrees or less above the horizon for it to be visible as a semicircular ring. Any higher and the phenomenon will theoretically fall below the horizon and disappear from view. 

(An antisolar point is a position on the celestial sphere situated directly opposite the sun from the observer's point of view.)

The semicircular ring visible above the horizon is only part of a full circle, which can be viewed in its totality if the observer is situated at an elevated position like a mountaintop.

Fogbows are almost as big as rainbows, but the ring (or bow) is much broader in size due to the amount of diffusion and light scattering by the small size of the droplets present in fog.

The following section will detail the process through which a fogbow occurs. 

How A Fogbow Occurs

Like a rainbow, a fogbow is observed with your back towards the sun while looking directly into a bank of fog in front of you.

  1. 1
    The microdroplets in fog diffract (bend) and break up the sunlight into its constituent spectral colors, which results in the familiar color pattern that is so unique to a rainbow.
  2. 2
    However, as the microdroplets in fog are a fraction of the size of raindrops (up to a hundred times smaller), they react and scatter sunlight differently than rainbows.
  3. 3
    The size of the droplets results in the formation of multiple smaller beams of spectral light reflected and scattered in all directions. Many of these smaller beams of lights come together, overlap, or merge to display a combined color of white.
  4. 4
    This process explains why a fogbow appears as a predominantly white ghostly semicircle. (Sometimes displaying spectral colors on the extreme side of the spectrum with a shade of red on its outer edge and blue on its inner edge.)

Fogbows Are All About Diffraction

The formation of a fogbow is also impossible to take place without the occurrence of a process known as diffraction.

spectral colors

As white light passes through a raindrop (as illustrated by the prism), refraction causes it to be broken up into its constituent spectral colors.

Diffraction is defined as the bending of light as it travels around or through an object. The diffraction of light as it passes through a raindrop is responsible for the breaking up of light into its spectral colors. We view these diffracted colors whenever observing a rainbow or fogbow.

The larger waterdrops in rain acts as a prism and break up (diffract) the sunlight into its constituent spectral colors, which is clearly visible in the resulting luminous rainbow.

Unlike rain, however, the smaller-sized droplets in fog cause less diffraction (bending) of light, which means a smaller separation into constituent spectral colors. 

This means the light viewed by the observer is seen as primarily white (the combination of all spectral colors).

The conditions and specific characteristics of any fogbow may vary from one occurrence to another. However, the process described here, as well as the requirements that need to be in place for the phenomenon to occur, always remains the same.


As this post clearly highlighted, the process that is responsible for the formation of a rainbow is identical to the one that creates a fogbow. The only real difference is the size of the droplets in a fog bank.

The size of these micro-droplets, though, completely changes the characteristics of a fogbow, displaying a semicircular ring stripped of all its color. It is unique and eyecatching in its own right and can produce a spectacular display under the right conditions.

This article explained what a fogbow is, described its characteristics, and went on to explain its formation in detail.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


Virga Rain: Explaining Virga And How It Occurs

Virga-Rain - Explaining What Virga Is And-How It Occurs

You may not have heard of virga before, but the chances are good that you already saw the phenomenon it refers to, more than once. 

This meteorological event is actually a very common occurrence and appears throughout the world wherever precipitation takes place.

If you ever observed a cloud and noticed wispy streaks of rain forming at its base, only to disappear into "thin air," you saw what is commonly known as virga. And your eyes are not deceiving you.

Even a weather radar can clearly identify the presence of rain in a cloud, yet nothing reaches the surfaces. It may seem inexplicable, but there is a very logical explanation for this event.

In this post, we look at what virga is, its characteristics, as well as how it forms. 

Virga Definition

The introduction already provided a clear indication of what virga entails. Before continuing, though, one needs to establish a concise definition of what precisely the phenomenon is. 

What Is Virga?

What Is Virga

Virga is a meteorological phenomenon where precipitation can be observed forming at the base of a rain cloud but disappear before reaching the ground as a result of evaporation or sublimation.

Simply put, virga is precipitation that forms at the base of a cloud but never reach the ground.  Depending on height, the type of precipitation can be solid (snow) or liquid (rain), but usually manifest in the form of rain.

The virga rain is visible as wispy light-colored streaks or tails that extend below the cloud base before disappearing in mid-air.

Virga clouds are also commonly known as jellyfish clouds due to their shape. The puffy structure and dark base of a cumulus type cloud represent the body, while the light streaks of rain below it resemble the tentacles of a jellyfish.

The types of clouds associated with this occurrence are, in general, the type that produces precipitation. They include cumulus, nimbostratus, cumulonimbus, stratocumulus, and altocumulus clouds.

How Virga Occurs

Rain forming at the cloud base level and then suddenly "disappear" in mid-air is quite common, as mentioned in the introduction. The reason you don't see it more often is that it does not always appear in view or at an angle, which makes it more visible.

The rain does not actually disappear. It merely changes from a liquid (rain) into a gas (water vapor) through a process of evaporation or sublimation, making it invisible to the naked eye.

The following steps provide a concise summary of how virga occurs in general:

  1. 1
    Clouds form when moist air cools down to the point of condensation. The resulting microdroplets making up a cloud, are also the source of precipitation.
  2. 2
    The microdroplets crash into each other and combine to form larger droplets of water. When they become too heavy, gravity causes it to fall to the ground as rain.
  3. 3
    In the case of virga, raindrops falling from a cloud usually encounters a layer of warm, dry air. The heat and lack of humidity in the air cause the rain to evaporate or sublimate (turning it back into its gaseous state).
  4. 4
    Evaporation takes place when precipitation changes from its liquid form to gas (raindrops to water vapor). Sublimation takes place when precipitation turns from its solid state directly into a gas (snow to water vapor).
  5. 5
    Virga typically occurs in deserts or other regions with low humidity. It also forms at high altitudes where small ice crystals quickly turn into water vapor as a result of adiabatic compression.
  6. 6
    Evaporation is a cooling process, meaning the virga rain that evaporates leaves a pocket of cold air behind. The cold air can accelerate to the ground at a rapid pace, resulting in a dry downburst, which creates dangerous, unstable weather.
  7. 7
    Unstable weather conditions also occur higher in the atmospheric where virga is the result of adiabatic compression. This heats the air, which causes pockets of warm & cold air at the same altitude, the perfect recipe for turbulent conditions.
  8. 8
    Virga rain is also known as fallstreaks due to its appearance and location beneath the cloud base.

Virga forms in many different ways, but the general steps in which it occurs as well as the characteristics it display, follow the same path as illustrated in the steps above. 


Virga is a common experience, observed almost everywhere precipitation takes place. The rain which drops halfway from the cloud base before disappearing remains a strange sight. This article, however, illustrated how the phenomenon occurs in a perfectly logical way.

The focus of this post was to explain what virga is, how it occurs, and highlight its most essential characteristics.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


Shelterbelt: Defining A Windbreak And How It Works

Shelterbelt - Defining A Windbreak And How It Works

Wind plays a crucial role in the development of weather occurrences throughout the world. Close to the ground, though, persisting wind activity can have an adverse effect on the surroundings. 

One can see the impact constant wind movement has on the environment through wind erosion occurring in different regions. Along the coast, exposed sand dunes retreat inland due to wind activity, while topsoil is removed from fertile land in increasingly arid territories.

Wind can also have a negative impact on agriculture. It can damage or even destroy entire crops, and also harm livestock that are sensitive to extreme temperatures. 

These are just a few examples where persistent wind activity is not only unwelcome but also damaging with potentially huge implications. Here, relatively simple but very effective human innovation comes into play. It is called a shelterbelt.

Shelterbelts are used throughout the world as an artificial barrier to protect against the harmful effects of wind activity... 

Shelterbelt Definition

Also known as windbreaks, shelterbelts serve a number of different purposes. The main objective always remains the same, though, which is to protect selected areas against potentially damaging wind forces.

Before describing how it works in more detail, one first needs to define what precisely a shelterbelt is:

What Is A Shelterbelt (Windbreak)?

What Is A Shelterbelt

A shelterbelt is a barrier of vegetation, usually consisting of lines of trees and shrubs, created to protect against the damaging effects of wind activity.

It used in agriculture to protect crops and livestock, as well in the environment, to guard against erosion, amongst others.

The main goal and purpose of shelterbelts are to reduce wind velocity dramatically. It accomplishes this task by planting one or more line of vegetation in the path of a prevailing wind to protect a selected area.  

The line of vegetation usually consists of a combination of trees and shrubs to be the most effective. Depending on the specific goal, several lines of vegetation can be planted to provide optimum protection.

The protected area downwind from the windbreak can vary from experiencing very little to no wind, based on the density and number of lines of the protective barrier. The windless region created by a shelterbelt is known as a wind shadow.

How A Shelterbelt Works

As stated in the previous section, a shelterbelt protects a specified area by significantly reducing or eliminating the wind speed over the protected region. The protected area can be a field of crops, livestock, or area of land that is vulnerable to wind erosion.

How A Shelterbelt Works

Illustration showing how a shelterbelt works. Click on image for a larger view.

The illustration above will assist in illustrating how a typical shelterbelt works in practice. Although the figures and measurements will differ from one type of windbreak to another, the fundamental principles remain the same.

The following fundamentals provide a thorough overview of the process through which a shelterbelt functions. 

  1. 1
    A shelterbelt is situated upwind (on the windward side) from the protected area.
  2. 2
    The windbreak is situated perpendicular (at a 90° angle) to the wind direction to provide maximum protection.
  3. 3
    The trees and shrubs used in shelterbelts are semi-permeable, which is crucial. A solid impermeable windbreak causes a sudden disruption of the wind flow. It results in turbulent instead of calm air on the leeward side of the barrier.
  4. 4
    As the moving air reaches the windbreak, pressure builds up on the windward side of the barrier. The majority of air is forced over the top of the shelterbelt. Some escape along the edges while the remaining air filters through the trees and shrubs.
  5. 5
    The wind traveling over the top of the windbreak accelerates to cause a jet of fast-flowing air. It travels aloft for a distance before descending back to the surface.
  6. 6
    The distance the air travels before dropping down is approximately 3-5 times the height of the shelterbelt.
  7. 7
    As a result, a calm area of low-pressure gets created on the leeward side of the windbreak. The length and amount of air movement in this sheltered location depends on the height and density of the shelterbelt.
  8. 8
    After descending back to the ground, the air that traveled over the sheltered region, regains momentum and speed.
  9. 9
    The air pressure at the surface also returns to normal at this point. It acts as a high-pressure buffer to further limit the movement of air within the protected area behind it.

Although differing in size and height, all shelterbelts form and function in the way describes in these steps.

The Purpose Of A Shelterbelt

As mentioned earlier in this post, a shelterbelt is used for a number of different purposes. The most notable application is in the agricultural sector to protect crops and livestock, but also in the environment to protect against wind erosion.

Purpose Of A Shelterbelt

The following list provides a concise summary of the primary applications of shelterbelts used for protecting and shielding different areas:

  • The first and most common use of windbreaks is the creation of barriers on farmland to protect crops. Strong winds will completely destroy young seedlings but are also to break and damage grown plants.
  • In warm weather, prevailing winds can dry out plants and soil, which can stunt their growth and cause permanent damage. In cold weather, the wind chill can lower temperatures to the point where crops can be damaged or even killed.
  • Shelterbelts are also used to protect livestock. Cold conditions caused by windchill cause animals to adjust to temperatures below their thermal neutral zone*, which results in weight loss and also hypothermia, which can be fatal.
  • Windbreaks play a crucial role in the protection of the environment. Placing these barriers in front of exposed land or other areas vulnerable to wind erosion protects and assists in restoring damaged regions.
  • Shelterbelts are also used to control snowdrifts. It is either used to stop snow from entering an unwanted area like a road or homestead or keep snowdrift in place. (The melting water from snow is useful in irrigating pieces of land.)
  • On a farm or other exposed area, a shelterbelt is used as a visual screen. It protects from being seen and potentially become a target of crime, and also mask unsightly objects like roads and buildings from its view. 

(* Thermal neutral zone is the temperature at which an animal experiences optimal health and performance.)


As this post clearly illustrated, shelterbelts or windbreaks are a simple but effective means of protecting against the damaging effect of prevailing winds. They also have a wide range of applications, varying from the practical to the aesthetical.

This article illustrated what a shelterbelt/windbreak is, how it works, as well as highlighted its various uses.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


Köppen Climate Classification: Defining The Climate Zones Of The World

Köppen Climate Classification

The plant and tree life of any region is a direct result of the prevailing weather it experiences. Similarly, the climate of an expansive terrain is primarily influenced by the underlying vegetation. 

The close correlation between climate and vegetation is evident in every part of the world. (The cold, dry conditions of Antarctica and the moist & humid conditions of the tropical rainforests in South America are just two examples of this powerful interaction.)

The strong connection between the two is also proving to play a key role in categorizing and dividing the global climate into more specific zones. Each climate zone is identified by its unique combination of vegetation, temperature, and precipitation.

These three variables are also determining factors in climate classification. During the late 19th Century, climatologist Wladimir Köppen used vegetation, temperature, and precipitation as the key components in developing the Köppen Climate Classification.

This post describes what the Köppen Climate Classification is, and also looks at the different climate zones it defines.

Köppen Climate Classification Definition

It is already clear that vegetation, temperature, and precipitation are the three main components involved in defining the Köppen Climate Classification.

Before looking in more detail at the different climate regions identified by this system, as well as the role each component play, one needs to obtain a clear and concise definition first of what the Köppen Climate Classification is:    

What Is The Köppen Climate Classification Definition?

What Is The Köppen Climate Classification Definition?

The Köppen Climate Classification is a widely-used classification system that divides the global climate into five climate zones primarily based on vegetation.

Developed by Wladimir Köppen at the end of the 19th century, the system uses precipitation and temperature as the two key components to classify the climate of a region, as they are the determining factors for the type of vegetation that occurs.

The close correlation between climate and vegetation, already mentioned in the introduction, forms the bases for this popular classification system.

Late in the 19th century, climatologist and botanist Wladimir Köppen developed a climate classification system based on vegetation. He used the correlation between vegetation and climate in different regions to divide the world's climate into specific zones.

The resulting Köppen Climate Classification categorizes the global climate into five distinct zones, primarily based on the temperature and precipitation experienced by each one.

Köppen continued to change and refine his classification system, with two of the most important amendments made in 1918 and 1936.

Climatologists continued to make amendments to Köppen's climate classification. Rudolf Geiger was probably the most influential in making important amendments, and the subsequent Köppen-Geiger Classification System is one of the most widely used today.

Climate Zones Of The World

According to the Köppen Climate Classification, the global climate can be divided into five primary zones. These climate zones are based on regional vegetation and defined by the temperature and precipitation that is responsible for its formation.

Koppen-Geiger Climate Map

Köppen-Geiger Climate Map depicting the 5 major climate zones and subcategories

The zones are defined by the capital letters A, B, C, D, and E. The climate zones defined by each letter are:

   A)  Tropical Climates

   B)  Dry Climates

   C)  Temperate Climates

   D)  Continental Climates

   E)  Polar Climates

Each of the five major climate zones covers a vast region and is divided into smaller categories to describe the more specific climate types within each zone.

To best understand each climate type and its characteristics, is to look at it within the primary climate zone in which it falls.

A)  Tropical Climates

Tropical Climate Zone

Tropical (also known as equatorial) climates occur in regions situated around the equator and expand to latitudes of 15° to 25° to the north and south. It can be defined by the following characteristics:

  • It is the warmest of all the climate zones.
  • Regions in this zone have an average monthly temperature of higher than 18° Celsius (64.4° Fahrenheit.) 
  • Annual precipitation exceeds 1 500 millimeters in this zone.
  • High humidity levels and warm temperatures result in a frequent, almost daily occurrences of cumulus or larger cumulonimbus cloud formations.

This zone is divided into three subcategories, which are classified according to temperature and dryness.

  1. 1
    Af - Tropical Rainforest Climate (no dry season.) 
  2. 2
    Am - Tropical Monsoon Climate (short dry season)
  3. 3
    Aw/As - Tropical Savanna Climate (winter dry season)

B)  Dry Climates

Dry Climate Zone

Dry (or arid) climates occur in regions situated at latitudes between 20° to 35° north and south of the equator. It can be defined by the following characteristics:

  • The main feature of this climate zone is the complete absence or extremely low levels of annual precipitation.
  • The very dry atmospheric conditions are the result of the combined evaporation and transpiration levels exceeding the total amount of precipitation.
  • Vegetation is sparse or completely absent as a result of the dry climate with very little precipitation.

This climate zone is divided into desert (BW) and semi-arid (BS) regions, according to vegetation type. It is further categorized into hot (h) and cold (k) zones:

  1. 1
    BWh - Hot Desert Climate
  2. 2
    BWk - Cold Desert Climate
  3. 3
    BSh - Hot Semi-Arid Climate
  4. 4
    BSk - Cold Semi-Arid Climate

C) Temperate Climates

Temperate Climate Zone

Temperate (or mesothermal) climates occur in regions situated at latitudes between 30° to 50° north and south of the equator. It can be defined by the following characteristics:

  • Regions in this climate zone typically experience warm summers with high levels of humidity and mild winter seasons. 
  • During the year, the warmest month is at least 10° Celsius (60° Fahrenheit) or higher, while the coldest month is lower than 18° Celsius (64.4° Fahrenheit) but higher than -3° Celsius (26.6° Fahrenheit).
  • These climate zones are typically located on the edges of continents, along the eastern and western coastlines.

Temperate climate zones are divided into three main categories according to precipitation: mild temperate dry winters (Cw), mild temperate dry summers (Cs), and mild temperate humid (Cf) climates. All three subcategories are further divided according to temperatures:

  1. 1
    Cfa - Humid Subtropical Climate
  2. 2
    Cfb - Temperate Oceanic Climate
  3. 3
    Cfc - Subpolar Oceanic Climate
  4. 4
    Csa - Hot-Summer Mediterranean Climate
  5. 5
    Csb - Warm-summer Mediterranean
  6. 6
    Csc - Cold-summer Mediterranean Climate
  7. 7
    Cwa - Monsoon-Influenced Humid Subtropical Climate
  8. 8
    Cwb - Subtropical Highland Climate
  9. 9
    Cwc - Cold Subtropical Highland Climate

D) Continental Climates

Continental Climate Zone

Continental climates typically occur in regions situated at latitudes between 40° and 75° north and south of the equator. (Although this type of climate is rare in the Southern Hemisphere.) It can be defined by the following characteristics:

  • The average temperature of the warmest month is above 10° Celsius (50° Fahrenheit), while the coldest month is below -3° Celsius (26.6° Fahrenheit).
  • This climate type is usually found in the interior of continents.
  • Regions in this zone experience summers with warm to cool temperatures, while the winters are generally cold.

Continental climate zones are divided into three main categories according to precipitation: continental dry summer (Ds), continental dry winter (Dw), and continental humid (Df) climates. Like temperate climates, they are further divided according to temperature:

  1. 1
    Dfa - Hot-Summer Humid Continental Climate
  2. 2
    Dfb - Warm-Summer Humid Continental Climate 
  3. 3
    Dfc - Subarctic Climate
  4. 4
    Dfd - Extremely Cold Subarctic Climate
  5. 5
    Dsa - Hot Dry-Summer Continental Climate
  6. 6
    Dsb - Warm Dry-Summer Continental Climate
  7. 7
    Dsc -  Subarctic Climate
  8. 8
    Dsd - Very Cold Subarctic Climate
  9. 9
    Dwa - Monsoon-Influence Hot-Summer Humid Continental Climate
  10. 10
    Dwb - Monsoon-Influence Warm-Summer Humid Continental Climate
  11. 11
    Dwc - Monsoon-Influence Subarctic Climate
  12. 12
    Dwd - Monsoon-Influence Extremely Cold Subarctic Climate​​​​​

E) Polar Climates

Polar Climate Zone

Polar climates are located at latitudes above 70° over the Arctic, Greenland, and Antarctica. It is characterized by its all-year-round cold temperatures and little to no vegetation. The following characteristics define it more precisely:

  • The warmest month of the year is below 10° Celsius (50° Fahrenheit).
  • Polar climate regions are extremely dry, with annual precipitation of less than 25 cm (10 inches).

Polar climates are divided into two categories according to vegetation: 

  1. 1
    ET - Tundra
  2. 2
    EF - Ice Cap Climate

Tundra Climates consist of very little vegetation (mainly loose shrubs, mosses, and dwarf trees) over a surface where the soil is frozen for several hundred meters. (A condition known as permafrost.) Ice Cap Climates are completely covered by ice or snow.


As clearly illustrated throughout this article, several smaller climate regions exist within each of the five major climate zones. Vegetation, temperature, and precipitation have been the key factors used in determining each subcategory.

Most countries throughout the world experience multiple sub-climates, and many larger regions are influenced by five or more different climate types at any given time. To explain all the climate zones affecting every country/region, though, will fill an encyclopedia. 

This post provided a broad and thorough overview of the five climate regions as defined by the Köppen Climate Classification. It highlighted the characteristics of each one, as well as laying out their subcategories and how they were defined. 

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!


Weather Rockets: A Special Kind Of Sounding Rocket

Weather Rockets - A Special Kind Of Sounding Rocket

Weather stations measure atmospheric conditions near the ground. Weather balloons take measurements in the stratosphere at heights of up to 40 km. But what if readings at greater altitudes are required? 

The vast majority of weather takes place in the lowest layer of the atmosphere, called the troposphere. A number of meteorological instruments measure these conditions, including weather stations, doppler radars, and weather buoys.

Above the troposphere, atmospheric conditions in the stratosphere are still of importance. It is usually measured by weather balloons that can measure a wide array of variables, including temperature, humidity, barometric pressure, and wind speed.

More often than not, the need arises for taking atmospheric readings at even higher altitudes. Weather balloons reach a maximum altitude of only around 40 km (25 miles). They also take almost an hour to reach this height.

This brings us to a special kind of sounding rocket called the weather rocket. These specialized meteorological projectiles literally fill the space between the maximum reach of weather balloons and the lowest orbit of weather satellites.

This post examines what a weather rocket is, its characteristics, as well as how it functions in more detail. It also takes a look at the larger sounding rocket category in which it falls.

Weather Rocket Definition

The introduction provided some clues as to what a weather rocket is, but leaves most questions unanswered. To start understanding this meteorological "device," one needs to address its classification as a type of sounding rocket first.

The best way to summarize the relationship between the two is with the following statement:

"All Weather Rockets Are Sounding Rockets, But Not All Sounding Rockets Are Weather Rockets"

This statement may sound very confusing, but it is actually easy to understand. Sounding rockets are simply a much broader (umbrella) term for a class of smaller projectiles with similar characteristics. Weather rockets fall within this category.

Sounding Rocket Definition

This explanation on its own is not specific enough. As a result, one needs a clear definition of a sounding rocket and its characteristics, before delving into the more specific subcategory of weather rockets:  

What Is A Sounding Rocket?

Sounding Rocket

A sounding rocket is a rocket-powered projectile that carries an instrument array 48 - 805 km (30 - 500 miles) into the atmosphere to conduct scientific testing or take atmospheric measurements.

Sounding rockets usually consist of solid-fueled single-stage rocket motors and a payload that carry an array of instruments (or objects for testing) into the upper atmospheric layers of the earth.

Also known as a research rocket, its primary use is to carry a payload up to an altitude of approximately 45 - 150 km above the planet's surface from where it can conduct dedicated experiments or take atmospheric measurements.

The main advantage of reaching these altitudes is that sounding rockets are capable of accessing the part of the atmosphere between that of high-altitude weather balloons and low-orbit satellites.

(Some advanced sounding rockets are multi-stage rockets that can reach altitudes that far exceed the height at which most satellites orbit the Earth. For example, NASA's Black Brant XII is a four-stage rocket that can reach an altitude of 1 500 kilometers or 932 miles).

The rockets follow a parabolic path with the highest point reached called the apogee. At or near the apogee, the payload/instruments experience a brief period of weightlessness before falling back to earth. It is in this space that most experimenting/testing takes place.

Sounding (or research) rockets are used for several different purposes, from testing instruments and materials that will be used in satellites or other spacecraft, gathering astronomical data, to taking atmospheric measurements.

And it is this last point that brings us to weather rockets.

Weather Rocket Definition

The previous section described the broader category within which weather rockets fall. Although every weather rocket is a type of a sounding rocket, certain characteristics differentiate it from similar projectiles.

Before looking at the features that make them unique, one needs to define what precisely a weather rocket is:

What Is A Weather Rocket?

Weather Rocket

A weather rocket is a specific type of sounding rocket (also known as a rocketsonde) that takes various meteorological readings in the upper atmosphere at altitudes of approximately 75 km (46.6 miles).

Also known as a meteorological rocket or rocketsonde, a weather rocket's primary purpose is to measure atmospheric conditions in the earth's upper atmospheric layers. (Mostly in the mesosphere, but also the thermosphere.)

The radiosonde on a rocket can measure several atmospheric variables, including temperature, humidity, air pressure, and wind speed. It all depends on the specific purpose of each rocket launch, which is not always purely meteorological.

(For example, multiple weather rockets are often used to determine upper atmospheric conditions before a large satellite or manned rocket launch.)

Weather rockets consist of a rocket booster and radiosonde that separates at a set height, from where the payload continues its ascent until reaching the apogee, where it descends with the assistance of a parachute while taking atmospheric measurements.

What makes a weather rocket especially important, is its ability to take weather readings at altitudes of approximately 75 kilometers (46.6 miles). This is well above the range of weather balloons, which reach a maximum height of roughly 40 km (25 miles.)

An increased altitude is just one of several advantage over weather balloons:

  1. 1
    While a weather balloon can take up to an hour to reach the correct altitude, a weather rocket can reach operational heights within a few minutes.
  2. 2
    Surface conditions can contaminate a balloon's radiosonde at its launch, which can interfere with readings at altitude. The enclosure of a weather rocket protects it from outside interference during launch.

How A Weather Rocket Works

The vast majority of weather rockets work on the same principles and operate in the same way. Some of the most well-known rockets ever used for measuring atmospheric conditions is the Loki series of sounding rockets.

By using the Super Loki variant as an example, one will be able to get a clear picture of how most weather rockets function. The following steps describe how a weather rocket operates and the path it follows, from launch until touchdown. 

  1. 1
    The single-stage rocket consists of two sections: The main rocket booster, and the radiosonde payload, situated in the dart/cone section of the projectile.
  2. 2
    After ignition, the rocket launches and accelerates rapidly to approximately Mach 5 (five times the speed of sound.) 
  3. 3
    At a height of 9 144 meters or 30 000 feet, the rocket motor and payload separates. The payload continues its ascent while the rocket motor falls back to the surface. 
  4. 4
    The payload section ascents to its apogee at a height of 76 200 meters or 250 000 feet. (Sounding rockets' apogee varies, depending on payload and rocket output.)
  5. 5
    After reaching maximum altitude, the payload section experiences a brief period of weightlessness before it starts to fall back to the ground.
  6. 6
    As it begins to fall back to the surface, a parachute is deployed to slow down and control the descent. The radiosonde starts to perform the majority of its measurements during this period.
  7. 7
    It takes a weather rocket approximately 2 minutes to reach its maximum height or apogee but can take more than 1.5 hours to return to the surface (with the assistance of a parachute.)
  8. 8
    Upon touchdown, the radiosonde array is retrieved for reuse at a later stage. The total amount of time spend 
Loki Dart Weather Rocket

Although these steps are generally based on the performance and characteristics of the Loki Dart rocket, it is typical of the way in which the majority of weather operates

Key Weather Rocket Facts

This post focused on providing a detailed definition of a weather rocket and the broader category of sounding rockets within which it falls. It also explored its characteristics and took an in-depth look at the steps involved in its operation.

The following list provides a concise summary and highlights the key information about a weather rocket.

  • A weather rocket is a specific type of sounding rocket that takes meteorological measurements in the upper atmosphere at altitudes of roughly 75 km (46.6 miles).
  • Sounding rockets are rocket-powered projectiles that carry instruments to heights of 48 - 805 km (30 - 500 miles) for scientific testing or atmospheric measurements.
  • Meteorological rockets are solid-fueled single-stage rockets that consist of two sections: The rocket motor and the radiosonde payload.
  • After launch, the rocket & payload separate at a set height. While the rocket motor falls back to earth, the instrument payload continues its ascent until reaching its apogee and then start taking measurements with the assistance of a parachute. 
  • Two of the biggest advantages of a weather rocket is the ability to reach greater altitudes than a weather balloon, as well as doing it in a fraction of the time.
  • All weather and sounding rockets follow a parabolic trajectory and experience a brief period weightlessness at their apogee before falling back to Earth.

Although this is not a comprehensive list of all the features and functions of a weather rocket, it highlighted the most important facts. The more detailed information is categorized and laid out throughout the rest of this article.


They may be as well-known as other meteorological equipment, but weather rockets play an essential role in measuring atmospheric conditions at altitudes beyond the capabilities of weather balloons. 

Weather rockets are just one category of sounding rockets. Sounding rockets are used in several different applications, from high-altitude material testing, zero-gravity experiments, to measuring atmospheric conditions before larger manned or satellite launches. 

The article, however, focused on defining a weather rocket, examine its characteristics, and looking at how it functions.

Never miss out again when another interesting and helpful article is released and stay updated, while also receiving helpful tips & information by simply  following this link .

Until next time, keep your eye on the weather!