Weather is sunshine, rain, snow, wind, and storms. It's what is going on outside right now. The weather is different at different places around the planet. In some places it's sunny right now, while in other places it's snowing. Many things affect the weather including the atmosphere, the Sun, and the season.
Wind on the Earth
On the Earth there is always an area of low pressure at the poles where the air is always cold. There is also higher pressure at the equator where the air is hot. These two major areas of air pressure keep the wind constantly moving about the Earth. The spin of the Earth also affects the direction of winds. This is called the Coriolis Effect.
Precipitation (rain and snow)
When water falls from clouds it's called precipitation. This can be rain, snow, sleet, or hail. Rain forms from the water cycle. The sun heats up water on the Earth's surface. Water evaporates into vapor and travels into the atmosphere. As more and more water condenses, clouds form. Eventually water droplets in clouds become large and heavy enough that gravity pulls them back to the ground in the form of rain.
We get snow when the temperature is below freezing and small ice crystals stick together to form snowflakes. Each snow flake is unique making no two snowflakes exactly alike. Hail generally gets formed in large thunderstorms where balls of ice get blown several times up into the cold atmosphere. Each time another layer of water on the ball of ice gets frozen making the ball larger and larger until it finally falls to the ground.
- (Ducksters) (More on Weather next week)
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