ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

Weather and Rain -Snowflakes and Raindrops

Updated on August 29, 2012

rainshowers and raindrops

Raindrops start out as cloud droplets
Raindrops start out as cloud droplets | Source


“If the rain spoils our picnic, but saves a farmer's crop, who are we to say it shouldn't rain?” ~Tom Barrett

Rain - it is all a matter of perspective. It usually interferes with the things we want to do (unless we want to take a walk in the rain). If we haven’t had rain for awhile, we do appreciate it.

We all know how important it is for the plants, for the crops, for the beauty of nature and for our existence. We often take rain for granted, but there is a delicate balance in nature for rain to form.

Read on and you may discover some interesting facts about this aspect of weather.

How Raindrops Form

Raindrops start out as cloud droplets.

In the middle of nearly every cloud droplet is a condensation nucleus. It is the nuclei that attract water.

Condensation nuclei are microscopically small, ranging in size from 0.0002 to 0.006 millimeters (0.000008 to 0.0002 inches) in diameter.

As small as these nuclei are, they are much bigger than any individual water vapor molecule. These ever so small nuclei are usually made up of dust, or salt that will attract the water to condense.

The dust and salt originate from the sea salt from the ocean, the soil, and from the burning of fossil fuels and vegetation.

As it begins to precipitate, they get washed out and cleansed from the air. A cloud forms from trillions of water vapor molecules that have condensed into millions of condensation nuclei.

The process of change of state from a vapor to a liquid is called condensation.

Why Do Cloud Droplets Turn into Raindrops?

There are 2 different ways cloud droplets can turn into raindrops.

Cloud droplets by themselves are so light, they stay in the air from the updrafts in the air.
One way is what is called collision and coalescence. The cloud droplets bump into each from the air current and it is called a co, llision. A coalescence is when they stick together after colliding. As they get big enough, they will fall to the ground.

It was Tor Bergeron, a Swedish meteorologist in the 1930’s who discovered the primary reason cloud droplets turn into raindrops.
The Bergeron Process explains that ice crystals attract the cloud droplets at the top of the clouds, making the ice crystals larger and larger. The air becomes saturated and the ice crystals join with each other to become snowflakes. The snowflakes become heavy enough to fall throught the warmer atmosphere, melt, and turn to rain as it hits the ground.

How Fast Do Raindrops Fall?

Since cloud droplets are so small they fall very slowly, about 0.2 mph or 1 cm per second.

Even the biggest of cloud droplets fall at the rate of 0.5 mph or 25 cm per second.

But raindrops, which can be 1 million times larger than cloud droplets, fall to the ground from the force of gravity at a speed of about 650 cm per second or 15 mph.

The average raindrops fall between 7 and 18 mph or 3-8 m per second. the range depends on the size of the raindrops.

If raindrops fall faster than 18mph, air friction will break up the raindrops.

Raindrops Usually Start Out as Snowflakes

Usually a raindrop starts out as a snowflake and melts as it falls towards warmer air.

Through evaporation, the raindrop can become cooler. Snowflakes can melt and refreeze as sleet, in winter air. In the summertime, a raindrop is often much cooler than the surface air temperature.

For rain and snow to form, tiny cloud drops or ice crystals merge and become heavy enough to fall. Most precipitation occurs because air over the oceans evaporate water.

Rain from the oceans is never salty because when the water evaporates the ocean water, the salt is not attached to it and so the salt stays in the ocean.

On occasion, when there is a hurricane, it can blow salty foam from the waves on land and the rain would be salty. The salty foam gets mixed with the rain, but is not really part of the rain.

Ring Around the Moon and Rain is on the Way

If you spot a ring around the moon, known as a halo, it may mean it is going to rain the next day.

The reason is, that cirrus clouds often precede a storm. If the cirrus clouds are then replaced by lower, thicker clouds, there is a good chance that snow or rain is coming.

The ring is really an optical illusion, created by tiny ice crystals 20,000 feet about the ground, that have formed thin wispy clouds.

The clouds are very very thin and thediffracted light from the brightness of the moon makes them appear as a ring or halo around the moon.

Freezing Rain, Sleet, Steady Rain, Showers, and Drizzling Rain

When rain falls from a cloud and evaporates before it reaches the ground, it is called virga.

There is a difference between freezing rain and sleet. Sleet is tiny pieces of ice that starts out as snow.The snow melts as the air it falls though gets warmer. Then the air gets thicker and colder, below freezing, and refreezes as an ice pellet.
Freezing rain starts out as snow also. It melts as it goes through warmer air and stays liquid (rain), When it hits the frigid ground, it freezes. .

A drizzle is rain that measures less than 0.02 inches in diameter, falling close together, usually from thin stratus clouds. The upward moving air current makes the droplets fall from stratus clouds before they have grown heavier.

The intensity of rain or drizzle is based on a visual estimate and on the amount of liquid that falls in 1 hour.

Rain usually falls a steady number of hours from a slow growing stratus clouds.

Showers develop through convection from cumuliform clouds. They start and stop suddenly, and the precipitation may be heavier.

Showering You With Facts

Some Interesting Facts About Rain:

  • Although there is no way of truly estimating how many drops of rain fall in an average storm, some meteorologists have estimated it to be about 1,620 trillion drops.

  • Rain consists of droplets that can be as big as 0.25 inches before they fall to the ground.

  • When a raindrop grows bigger than about ¼ inch in diameter, it usually breaks up into smaller raindrops.

  • Raindrops are not teardrop shaped. Rain drops are round until they grow too big. The air pressure pushes on the bottom of bigger raindrops, giving them a shape similar to a hamburger bun.


    0 of 8192 characters used
    Post Comment

    • Ruby H Rose profile image

      Maree Michael Martin 

      6 years ago from Northwest Washington on an Island

      Of course I love your cloud pictures! Thanks for a great explanation on rain. That is so cool to know!

    • kashmir56 profile image

      Thomas Silvia 

      6 years ago from Massachusetts

      This is such a great hub and some of this information i did know so thanks for helping me learn more about the weather and rain .

      Vote up and more !!!

    • kissayer profile image

      Kristy Sayer 

      6 years ago from Sydney, Australia

      It's hubs like these that save me when I get asked "Kristy.... why does it rain" - I can't answer all the questions the kids I nanny give me, but now I can tell them about the weather :P

    • billybuc profile image

      Bill Holland 

      6 years ago from Olympia, WA

      Maybe I'm a nerd but I always find these facts interesting...of course, I taught science so that might explain it.

      Great hub; very interesting my friend.


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)