Which cloud is described as billowy, low-level clouds with flat bases?

Which cloud is described as billowy, low-level clouds with flat bases?

• A. Cumulus
• B. Stratus
• C. Cirrus
• D. Nimbostratus

Answer: (A)

Billowy, low-level clouds with flat bases are cumulus. They form when warm air near the surface rises (convection) and cools to its dew point, condensing into droplets. The rising air creates those rounded, fluffy masses with a distinct, flat bottom where saturation first occurs. This gives the classic cotton-ball appearance and usually signals fair weather when small, though they can grow taller into storm-producing clouds if the atmosphere is unstable. The other types describe different forms: stratus are flat, gray layers that blanket the sky; cirrus are high, thin, wispy strands; nimbostratus are thick, dark rain clouds with a widespread, featureless base.

Billowy, low-level clouds with flat bases are cumulus. They form when warm air near the surface rises (convection) and cools to its dew point, condensing into droplets. The rising air creates those rounded, fluffy masses with a distinct, flat bottom where saturation first occurs. This gives the classic cotton-ball appearance and usually signals fair weather when small, though they can grow taller into storm-producing clouds if the atmosphere is unstable. The other types describe different forms: stratus are flat, gray layers that blanket the sky; cirrus are high, thin, wispy strands; nimbostratus are thick, dark rain clouds with a widespread, featureless base.