Cirrus: High, thin, wispy clouds made of ice crystals
Cirrostratus: High, thin sheet that can make a halo around the Sun
Cirrocumulus: High, small rippled clouds in rows
Altostratus: Middle-level gray or blue-gray sheet that can cover the sky
Altocumulus: Middle-level puffy patches in rows
Stratus: Low gray layer like fog above the ground
Stratocumulus: Low, lumpy gray and white clouds
Nimbostratus: Thick, dark layer that brings steady rain or snow
Cumulus: Fluffy white clouds with flat bottoms
Cumulonimbus: Tall thunderstorm clouds
Which cloud makes thunderstorms?: Cumulonimbus
Which cloud usually means fair weather?: Cumulus
Which clouds are the highest?: Cirrus family
Which clouds are low-level?: Stratus, stratocumulus and nimbostratus
What does cirro- mean?: High, wispy or curly
What does stratus mean?: Layer or sheet
What does cumulus mean?: Heap or pile
What does nimbus mean?: Rain-bearing
What does alto- mean?: Middle level
Contrail: A cloud-like trail left behind by a high-flying airplane
Fog: A cloud that touches the ground
Mist: A thin fog with tiny water droplets
Lenticular cloud: A smooth, lens-shaped cloud often near mountains
Mammatus cloud: Pouch-like bulges on the underside of a cloud
Noctilucent cloud: Very high thin cloud that glows at twilight
Anvil cloud: The flat top of a cumulonimbus
Funnel cloud: A rotating cone of cloud that hasn't touched the ground
Shelf cloud: Low wedge-shaped cloud at the front of a storm
Wall cloud: A lowered cloud base under a storm that can produce tornadoes
How do clouds form?: Rising air cools and water vapor condenses on tiny particles
What are clouds made of?: Tiny water droplets or ice crystals
Why do clouds float?: The droplets are so tiny that rising air keeps them up
Condensation nuclei: Tiny bits of dust or salt that droplets form on
Cloud cover: How much of the sky is covered by clouds
Overcast: A sky fully covered by clouds
Partly cloudy: A sky with some clouds and some blue
Why are clouds white?: They scatter all colors of sunlight
Why are storm clouds dark?: They are so thick that little light passes through
Cumulus humilis: Small, flat fair-weather cumulus
Cumulus congestus: Tall towering cumulus that can grow into storms
Mackerel sky: Cirrocumulus or altocumulus that looks like fish scales
Mares' tails: Long streaks of cirrus clouds
Halo: A ring of light around the Sun or Moon from ice crystals in thin clouds
Virga: Rain that evaporates before reaching the ground
Altitude of high clouds: Above about 6 kilometers
Altitude of low clouds: Below about 2 kilometers

Free flashcards from Peabody at peabody.kids/flashcards/earth-clouds