Weather Basics

Start with the atmosphere and the measurements meteorologists use every day.

About Weather Basics

Weather describes short-term atmospheric conditions such as temperature, wind, humidity, cloud cover, precipitation, and air pressure. These conditions are driven mainly by uneven heating from the Sun and the movement of air and water around Earth.

Visual learning: These pages use real Wikimedia Commons and scientific weather imagery. Final image URLs should be browser-tested before deployment.

Thunderstorm — ThunderstormThunderstorms form when warm moist air rises into an unstable atmosphere.

Tornado — TornadoTornadoes are rapidly rotating columns of air connected to thunderstorms.

Hurricane — HurricaneTropical cyclones are organized rotating storm systems fueled by warm ocean water.

Snowstorm — SnowstormWinter storms can combine snow, wind, cold, and low visibility.

Temperature

Temperature measures how warm or cold the air is.

Air Pressure

Air has weight and pushes on surfaces.

Humidity

Humidity describes water vapor in the air.

Wind

Wind is moving air.

Clouds

Clouds form when water vapor condenses or freezes onto tiny particles.

Precipitation

Rain, snow, sleet, and hail all move water from clouds to the ground.

Fronts

Fronts are boundaries between air masses.

Observation

Weather is measured continuously.

Temperature

Sunlight, clouds, altitude, wind, humidity, surface type, and time of day all influence temperature.

Air Pressure

Differences in pressure help drive wind and organize weather systems.

Humidity

Relative humidity depends on both the amount of water vapor and air temperature.

Wind

It flows because pressure differences create forces, while Earth's rotation and surface friction alter direction and speed.

Clouds

Cloud type can reveal information about atmospheric stability and moisture.

Precipitation

The temperature structure from cloud to surface determines what reaches the ground.

Fronts

Cold, warm, stationary, and occluded fronts are associated with different weather patterns.

Observation

Stations, radar, satellites, balloons, ships, aircraft, and citizen observations feed forecasting systems.