Fourth Grade
Worksheets
What Is Weather?
Weather is a mix of things that happen from day to day in the air (atmosphere) around the Earth. Rain, heat waves, and snow are examples of weather. Earth's air moves. It carries water vapor in it. Air has weight. The weight of air is called air pressure. Air pressure changes from place to place. Warm air weighs less than cold air. Warm air can carry more water vapor (which might turn into rain). Warm air rises. Cooler air falls. This movement of air causes wind. Wind, air pressure, heat, and water vapor. These four things cause different kinds of weather in different places at different times.
We can measure many things about the weather. We can measure how hot or cold it is. We can measure the speed of the wind. We can measure how much water vapor is in the air. We can measure the air pressure. All of these things can give us an idea of what the weather will be like in the near future.
