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The air around the earth is called the atmosphere.
Exosphere - The last layer and the thinnest. It goes all the way to 10,000 km above the Earth's surface. Thermosphere - The thermosphere is next and the air is very thin here. Temperatures can get extremely hot in the thermosphere. Mesosphere - The mesosphere covers the next 50 miles beyond the stratosphere. This is where most meteors burn up upon entry. The coldest place on Earth is at the top of the mesosphere. Stratosphere - The stratosphere extends for the next 32 miles after the troposphere. Unlike the troposphere the stratosphere gets its heat by the Ozone Layer absorbing radiation from the sun. As a result, it gets warmer the further away you get from the Earth. Weather balloons go as high as the stratosphere. Troposphere - The troposphere is the layer next to the ground or surface of the Earth. It covers around 30,000-50,000 feet high. This is where we live and even where planes fly. Around 80% of the mass of the atmosphere is in the troposphere. The troposphere is heated by the surface of the Earth.
Weather happens in the bottom layer of the atmosphere called the troposphere.
Weather comes from two things: the sun and the moisture (wetness) in the air. They form clouds, to make rain and cause winds to blow.
In cold air in the sky, rain clouds form.
Warm air rises up from the Earth. It carries water vapor from the ocean, lakes and rivers into the sky.
Then the water vapor cools and tiny water drops form around the tiny specs of dust in the air.
They bang together and grow in size until they're heavy enough to fall. This is rain.
There are three main types of clouds:
Cumulus clouds look like a heap of cotton balls or whipped cream.
Stratus clouds look like a flat blanket in the sky.
Cirrus clouds look like curls of white hair.
Snowflakes form when water vapor freezes into ice crystals in cold clouds.
They get heavy and fall. If the air is cold enough, the snow falls all the way to the earth without melting.
If the ground is freezing, the snowflakes stick to the ground.
click to see compacted snow
When warm air and cold air get together in thunder clouds it forms static electricity. This big charge of electricity can travel to the ground or to other clouds.
Lightning is over 40,000 degrees. So a bolt of lightning makes the air around it get bigger. Thunder is the sound caused by the air growing bigger.
