Clouds and precipitation

Precipitation can occur when droplets grow inside clouds. Exam tip: keep the difference between possibility and certainty.

Dry lower air can evaporate falling drops before they reach the ground. Exam tip: separate falling from cloud and reaching the ground.

Cumulus clouds are heap-like while cirrus clouds appear fibrous at height. In exams, identify them by shape.

When droplets become large and heavy, gravity makes them fall. In exams, treat droplet growth as a condition for precipitation.

Mountains force moist air upward, causing cooling, condensation, and rain. In exams, link windward slope with more rainfall.

On the leeward slope, air may descend, warm, and become dry. In exams, connect rain shadow with the opposite side of orographic rainfall.

Air above a strongly heated surface rises, cools, and forms clouds. In exams, take heat and rising air as clues.

In cyclonic conditions, convergence and uplift can form clouds and rain. In exams, remember low pressure and uplift.

Particles like dust, salt, and smoke act as bases for droplet formation. In exams, treat nuclei as helpers of condensation.

Stratus clouds can cover a large area as a layer. In exams, identify stratus with sheet-like clouds.

Nimbus is a term associated with rain-bearing clouds. In exams, remember nimbus as a rain indicator.

Cumulonimbus clouds grow vertically and create strong convective activity. In exams, link thunder with vertical growth.

Drizzle is light precipitation made up of very small, nearly uniform water droplets. In normal rain, drops are usually larger and the rainfall intensity may be greater. Falling ice particles refers to other forms of precipitation, such as snow or hail, not drizzle. Exam tip: identify drizzle by its very fine liquid droplets and low intensity.

For snowfall, ice particles must reach the ground without melting. In exams, link a cold air column with snowfall.

Hail can form in cumulonimbus clouds with strong vertical currents. In exams, connect hail with storm clouds.

Droplet joining increases their size and weight. In exams, link coalescence with rain formation.

Because of low temperature at height, water may exist as ice particles. In exams, connect height and cold with cirrus.

Condensation forms clouds, while precipitation is the falling stage. In exams, understand both in sequence.

Nimbostratus clouds are widespread and can give long-duration rain. In exams, link continuous rain with nimbostratus.

Dense water-rich clouds transmit less light, so they appear dark. In exams, link dark clouds with density and rain chance.