How Weather Works

weather
Rain and dull clouds, windy blue skies, cold snow, and sticky heat are very different conditions, yet they are all weather.
global map of clouds

Even with disruptions like weather fronts and storms, there is a consistent pattern to how air moves around our planet’s atmosphere. This pattern, called atmospheric circulation, is caused because the Sun heats the Earth more at the equator than at the poles. It's also affected by the spin of the Earth.

pressure gauge
How do we know what the pressure is? How do we know how it changes over time? Standing on the ground and looking up, it might not look like anything is there, especially if there are no clouds in the sky. But what you don’t see is air – lots of it. We live at the bottom of the atmosphere, and the weight of all the air above us is called air pressure.
Wind sock on pole
Wind is air moving from a place that has higher pressure to one that has lower pressure. Sometimes wind is just a light breeze and other times it is strong enough to blow the roofs off buildings.
The amount of water vapor in the air is called humidity.
Water can be in the atmosphere, on the land, in the ocean, and underground. It moves from place to place through the water cycle.
NOAA weather forecast map
Learn about weather map symbols and how they are used to make predictions of the weather.
Weather Fronts
When a front passes over an area, it means a change in the weather. Many fronts cause weather events such as rain, thunderstorms, gusty winds and tornadoes.
How does the atmosphere change at you go up high in the sky?
Weather Glossary
A glossary of common weather related words.