Cirrus Clouds

• Above 6000 m• Means “curly”• ice crystals

Cirrus

• Sunlight passes through easily

Cirrocumulus

• Form before or after a snowfall or rainfall.

Cirrostratus

• Halo appearance around sun or moon.

• Bending of light rays as they pass through the ice crystals.

• May thicken and lower to turn into altostratus clouds.

Stratus Clouds

• Means “sheet-like” or “layered”

• low clouds• Form when warm,

moist air lies below a layer of cold air.

• Often block out sun.• Cover large areas.

Nimbostratus

• Nimbo means “rain”• Bring heavy rains or

snow.

Cumulus

• Means “piled” or “heaped.”

• Form due to warm, moist air rises and cools.

• Height of cummulus depends on speed of upward movement and moisture in the air.

Cumulus

• Lots of moisture rises.

Billowing Cumulus

• Will develop into a cumulonimbus cloud.

Cumulonimbus

• Thunderhead• Rain• Lightning• Thunder

Altocumulus

Stratocumulus

Fog

• Low level stratus cloud.

• Radiation fog or “ground fog.

Steam Fog

• Fog over James River.• Land on other side of

bridge, no fog.• Forms near lakes or

rivers where cool air meets warm water.

Upslope fog

• Forms when air cools as it rises along landslopes.

Advection Fog

• Warm moist air goes over cool land.