WeatherTalk: Air pressure is fundamental to forecasting

Air pressure patterns across a region indicate areas of sinking or rising air, which is directly related to weather.

Cartoon of John Wheeler with a speech bubble depicting weather events
We are part of The Trust Project.

Barometric pressure is a routinely measured aspect of the atmosphere with a critical role in weather forecasting. Essentially, air pressure is proportional to the weight of the air above a point. Although the air pressure reading at any single point has little bearing on the weather, air pressure patterns (higher and lower) across a region indicate areas of sinking or rising air, which is directly related to weather. Downward-moving air generates clear weather, whereas rising air makes clouds and precipitation.

To be able to forecast how these patterns of pressure will change over time is critical to weather forecasting. This is why a falling pressure or a rising pressure is a telling sign. Differences in pressure across distances force air to move to attempt to equalize these pressures, so differences in air pressure are the primary reason the wind blows.

Related Topics: WEATHER
John Wheeler is Chief Meteorologist for WDAY, a position he has had since May of 1985. Wheeler grew up in the South, in Louisiana and Alabama, and cites his family's move to the Midwest as important to developing his fascination with weather and climate. Wheeler lived in Wisconsin and Iowa as a teenager. He attended Iowa State University and achieved a B.S. degree in Meteorology in 1984. Wheeler worked about a year at WOI-TV in central Iowa before moving to Fargo and WDAY..
What to read next
This warm blob has been created by a large region of high pressure in the atmosphere.
The West African Monsoon season is likely to start generating large tropical waves.
Air is not heated up very much by sunlight.
StormTRACKER Meteorologist John Wheeler discusses the August forecast