

Did you know?
All rain starts with the sun.
Did you know?
There are places in the Atacama desert which haven't seen rain for 400 years.
How it rains.
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The sun heats up the air.
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Warm air rises.
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As the air rises, it cools.
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The water vapour held in the air condenses back into water. If the air rises far enough, the water vapour might turn into ice crystals.
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If enough condensation occurs, a cloud will form, which is made up of billions and billions of little drops of water.
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Eventually the water held in the air becomes too heavy to be held up by rising currents of air and it falls to the ground as rain, or snow, if it is really cold.
Definition of rain
The condensed moisture of the atmosphere falling visibly in separate drops.
Synonyms for rain
Rainfall, precipitation, rain drops, wet weather, sprinkle, drizzle, mizzle, scotch mist, shower, rainstorm, cloudburst, torrent, downpour, deluge, squall, thunderstorm

Heavy
rainfall

Types of rain
There are three main types of rainfall: convectional rain, frontal rain and relief rain.
Rain is formed when air rises and so there are three ways of making air rise: by going over a mountain (relief rain), by rising through to being heated by the sun (convectional rain) and a warm body of air rising over a cold body of air (frontal rain).
Relief rain
Convectional rainfall
frontal rain
Rainfall facts
Wettest place on earth
In 1985, the Khasi Hills region of Meghalaya State in India received 26,000 mm of rain. A world record.
Rainfall facts
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Rain drops can vary in size from 0.5 mm across to 8 mm across.
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Rain falls to the ground at 35 km an hour.
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Antarctica is the driest continent on Earth.
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Heavy rain can cause flooding and landslides
Driest place on Earth
There are parts of the Atacama desert which have never recorded rain.
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The most rain to fall in one day fell during a hurricane.
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Rain can mix with pollutants in the air to form Acid rain and this is harmful to wildlife.
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Water can fall as rain, as sleet, as snow or as freezing rain.
Measuring the rain
How do we
measure the rain?
We measure the rain using a rain gauge. It measures the rain over a set period of time.
What do we measure
the rain with?
Modern rain gauges are self recording and automatically measure the rain in 5 minute intervals. This rain gauge is solar powered for working out in rural areas.
Freezing rain
Freezing rain
Freezing rain
Cause
Freezing rain is super cooled rain that freezes on impact. Helped along by the fact that the ground is also below freezing.
Effects
This rare event can be costly and create a lot of damage. Pulling down electricity wires and telephone wires and making roads extremely dangerous is the biggest headache caused by freezing rain.
WHY DOES IT RAIN?
