Clouds Leaflet No. 4. ©2013 by Andrew Schuerger. Licensed for use in one classroom.

What is a cloud? 1)When water evaporates, ‘water vapor’ is not visible. 2)When water vapor condenses into water droplets or ice crystals, it becomes visible. 3)Clouds are visible water droplets or ice crystals in the sky. 4)Clouds can form over water or land.

The Water Cycle 1)Water evaporates from oceans and land surfaces. 2)Water vapor rises into the atmosphere and begins to cool. 3)As the water cools it begins to condense into small water droplets or ice crystals. 4)Water droplets and ice crystals form clouds. 5)Once the clouds have enough water, rain or snow begins to fall. 6)Precipitation then collects on the surface and begins the Water Cycle again.

There are many types of clouds. Here are a few examples. Let’s look at six different types of clouds.

(1) Cumulus clouds are white and puffy.

(2) Cirrus clouds are thin and wispy.

(3) Nimbostratus clouds are small rain clouds. rain

(4) Cumulonimbus clouds are BIG rain clouds.

(5) Stratus clouds are uniform horizontal layers of clouds.

(6) Fog is a cloud that forms near the ground.

How do thunderstorms form? 1)Thunderstorms start out as small cumulus clouds. 2)As more moisture enters the atmosphere, the cumulus clouds begin to build into larger and higher clouds forming cumulonimbus clouds. 3)As more and more rain falls from the cumulonimbus clouds, the cloud gets smaller and eventually it stops raining.

Young nimbostratus clouds building into a towering cumulonimbus cloud. Nimbostratus clouds forming into a cumulonimbus thunderstorm.

Mature cumulonimbus cloud forming an anvil top. Nimbostratus clouds forming a cumulonimbus thunderstorm with an anvil top. The colors on the arrows equal the names of the clouds. anvil

Mature cumulonimbus cloud forming an anvil top. Thunderstorm Anvil Thunderstorm

Thunderstorms can produce lightning, rain, hail, tornadoes, or all four.

How does hail form? 1)Violent updrafts in cumulonimbus rain clouds keep ice particles suspended in the cloud. 2)The ice crystals continue to increase in size. 3)Once the updraft winds stop, the larger crystals fall from the clouds as hail.

Guess the cloud type. **Look at the Notes for the answers.

Guess the cloud type.

Resources 1)National Hurricane Center: 2)The Weather Channel: 3)The Weather Underground: 4)NOAA National Weather Service Radar: 5)NOAA’s photo-library: 6)NOAA Ocean Research: The information, photographs and illustrations presented here were obtained from several governmentwebsites: a) NOAA = National Oceanic and Atmospheric Administration [ b) NASA = National Aeronautics and Space Administration [ c) NWS = NOAA National Weather Service [ Additional Websites