Clouds and precipitation

On the leeward slope, air may descend and become dry, causing low rainfall. In exams, link rain shadow with mountains.

On the windward slope, moist air rises and condenses. In exams, connect windward slope with more rainfall.

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

Temperature is lower at height, so ice particles can form. In exams, connect height and cold together.

Small white cumulus clouds can appear in fair weather. In exams, connect them with fair weather signs.

Small droplets join to become larger and fall when heavy. In exams, link droplet joining with rain formation.

Rain and snowfall are both water forms falling from the atmosphere to the ground. In exams, identify forms of precipitation separately.

When air cools, it can become saturated and form droplets. In exams, treat cooling as a condition for condensation.

Pressure decreases with height, so air expands and cools. In exams, remember rising and cooling together.

The name nimbus is associated with rain-bearing clouds. For example, nimbostratus can produce continuous rain, while cumulonimbus may bring heavy rain and thunderstorms. Cumulus clouds may grow into rain clouds, but their name itself does not mean rain. Exam tip: associate “nimbus” directly with precipitation.

In evaporation, liquid water changes into water vapour. In exams, link it with the start of the water cycle.

Water vapour condenses into tiny droplets or ice particles. In exams, remember condensation after evaporation.

In precipitation, water comes from clouds to the ground in different forms. In exams, link precipitation with falling water.

In cyclonic rainfall, meeting and lifting of air masses can form clouds. In exams, link air-mass meeting with cyclonic rain.

Stratus clouds spread as layers in the sky. In exams, connect layered spread with stratus.

Cirrus clouds generally form at very high altitudes in the upper atmosphere. They are thin, white and wispy, and are mainly made of ice crystals. Stratus and stratocumulus clouds usually occur at lower levels, while cumulus clouds commonly form at low to middle levels. Exam tip: associate thin, feathery high clouds with cirrus clouds.

Cumulonimbus clouds can grow very high and bring stormy weather. In exams, link vertical growth with cumulonimbus.

Very light rain with fine drops is called drizzle. In exams, connect fine rainfall with drizzle.

Water from rain or snow can increase soil moisture. In exams, link precipitation with water availability.

As droplets grow, they can become heavy and fall. In exams, treat droplet growth as a condition for rain.