1. Your Cloud Encyclopedia
16-2 Notes on Clouds

2. Cirrus Clouds High, ice-crystal clouds Look like wispy curls of hair
Look feathery
Often the first signs of approaching weather changes

3. Cirrus Cloud Picture

4. Stratus Low clouds Usually covers whole sky
Gray blankets of clouds which often bring drizzle
Can cover high ground and cause hill fog.

5. Stratus Cloud Picture

6. Cumulus
Clearly defined puffs of fluffy clouds that look like "cauliflowers".
Look like cotton balls.
They appear in sunny, summer skies.
In the morning, they precede a storm, in the afternoon they follow a storm.

7. Cumulus Cloud Picture

8. Cloud Height Clouds are also described by their height
Cirro = high cloud height
Alto = middle cloud height
Strato = low cloud height

9. Cloud Height
Cirros (high) or Cirro can be used with cumulus (heap, puffy) to indicate a cirrocumulus or high, puffy cloud. It can also be used with stratus (flat, layered) as in cirrostratus to indicate a high, flat or layered cloud.
Alto can also be used with cumulus and stratus to indicate altocumulus and altostratus which are middle altitude puffy clouds and middle altitude flat or layered clouds respectively.

10. Cirrocumulus Often called a "mackerel sky“
the clouds' ripples of cloud looks like fish scales
indicates unsettled weather
form above 18,000 feet
appear as small, rounded white puffs that are isolated or in long rows. When the white puffs are in rows, they give the cloud a rippling appearance that distinguishes it from a cirrus or a cirrostratus cloud.
rarely cover the entire sky

11. Cirrocumulus Cloud Pictures

12. Cirrostratus form above 18,000 feet.
Sheets of thin, milk-colored clouds
form high up and often bring rain or snow within twenty-four hours
They often cause the sun or moon to appear to have a halo around it.
Sometimes these clouds are so thin that the only clue to their presence is a halo around the sun or moon.

13. Cirrostratus Cloud Picture

14. Cirrostratus Cloud Picture

15. Altostratus Layers of thin, gray clouds Can grow into rain clouds
These gray or bluish-gray clouds form between 6,000 and 20,000 feet.
Cover the entire sky over an area that usually extends over hundreds of square kilometers.
The sun may be visible under thinner sections of the cloud as a dim, round disk, known as a "watery sun“
Usually form ahead of a storm producing widespread and mostly continuous precipitation.
Altostratus clouds do not allow enough sunlight to break through the cloud to form any shadows on the ground.

16. Altostratus Cloud Picture

17. Altostratus Cloud Picture

18. Altocumulus Fluffy waves of gray clouds
Can bring showers or break up to give sunny periods
These clouds form between 6,000 and 20,000 feet and
Appear as gray, puffy blobs, sometimes rolled out in parallel waves or bands.
One part of the cloud is usually darker than the rest, which helps distinguish this cloud from the higher cirrocumulus clouds.
Look like "little castles" in the sky indicate rising air at the cloud level. The appearance of these clouds on a warm, humid

19. Altocumulus Cloud Picture

20. Altocumulus Cloud Picture

21. Stratocumulus
Uneven rolls or patches of clouds across the sky which follow a storm
Usually a sign that drier weather is on the way.
These low, lumpy cloud layers form below 6,000 feet
Can appear in rows, patches or as rounded masses with blue sky in between the cloud elements.
Color of stratocumulus clouds can range from white to dark gray.

22. Stratocumulus Cloud Picture

23. What’s A Nimbo? Nimbo meaning in latin rain
Nimbus clouds are the very dark storm clouds that have precipitation.

24. Nimbostratus
Thick, dark gray masses of clouds which can bring rain or snow.
These dark gray clouds usually form below 6,000 feet.
Are almost always associated with continuous light to moderate precipitation.
Often can last for several hours to more than a day.
The sun and moon are not visible through a layer of nimbostratus clouds. These clouds usually form in a stable atmosphere where warm, moist air.

25. Nimbostratus Cloud Picture

26. Nimbostratus Cloud Picture

27. Cumulonimbus
These are towering clouds which usually bring thunderstorms with rain, snow or hail. 
High winds will flatten the top of the cloud into an anvil-like shape. The anvil usually points in the direction the storm is moving.
Watch for cumulus (puffy) clouds that start to rapidly develop vertically (up) to become cumulonimbus thunderstorm clouds.
Fronts are often called thunderheads.

28. Cumulonimbus Cloud Picture

29. Cumulonimbus Cloud Picture

30. Cumulonimbus Cloud Picture