Low-Level Clouds

Below 2km

Cumulus

• Cumulus means heap or pile
• Traditional fluffy clouds
• Associated with fair weather but occassional showers
• Developed from convection

Cumulonimbus

• Usually the tall fluffy clouds making soft anvil shape
• Nimbus means rainy cloud
• Heavy rain and thunderstorms
• Only cloud that can produce hail, thunder and lightening
• Developed from convection

Stratocumulus

• Status means flat layer
• Light showers at most
• Usually gaps
• Usually developed from a layer of stratus cloud breaking up due to change in conditions

Stratus

• Flattened, spread out clouds
• Lowest lying, can form mist and fog
• Form from stable conditions
• Dependent on thickness, light drizzle

Mid-Level Clouds

2km to 6.5km

Altostratus

• Alto means mid level
• No precipitation
• Dull, featureless clouds covering the landscape in a thin layer
• Water and Ice
• Usually formed from a descending cirrostratus cloud

Nimbostratus

• Dull, featureless clouds covering landscape in thick layer
• Continous precipitation
• Develop from burgeoning altostratus clouds

Altocumulus

• No precipitation
• Ice and Water
• Bands/patches of mid level fluffy clouds
• Formed from broken altostratus, convection, mountainous topography to produce the wave-like features

High Level-Level Clouds

Above 6.5km

Cirrus

• Cirrus means wispy
• Ice only
• Formed by ascent of dry air, causing sublimation
• Seen all year round
• No precipitation

Cirrostratus

• Wispy flat layer, can span thousands of miles
• Ice only
• Formed by slow air ascent
• Indicator of weather as usually forefront of weather systems
• No precipitation

Cirrocumulus

• Ice and Supercooled Water
• No precipitation
• Formed from cirrus layer disturbed by turbulent vertical currents