Weather measurement for pressure

Atmospheric pressure is the force exerted at any given point on the Earth’s surface by the weight of the air above that point - the pressure is lower as you ascend higher into the sky. The air pressure at sea level at a temperature of 59°F (15°C) is equal to one atmosphere (Atm), and this is the baseline reading for determining relative pressure.

Atmospheric pressure is measured by an instrument called a barometer. When the air is dry, cool, and pleasant, the barometer reading rises. In general, a rising barometer means improving weather. In general, a falling barometer means worsening weather. When atmospheric pressure drops suddenly, this usually indicates that a storm is on its way. When atmospheric pressure remains steady, there will likely be no immediate change in the weather.

Start here: https://en.wikipedia.org/wiki/Atmospheric_pressure

Hi Ashtonplacecircle,

Thank you for using the Apple Support Communities! Check out this article that list all the data sources used in the Weather app that can help:

Feature availability and data sources in the Weather app

Hope this helps!

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