The air moving away from the High pressure system leaves a “hole” to be filled, so air from above sinks into that “hole”.
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High Pressure Systems

Have you ever seen a weather map with a blue H on it? This blue H means there is a high pressure system over that area of the map. Just what does that mean?

It means that that area has higher pressure then the air around it.

When there is a High above your house, you should expect clear skies and no rain or snow! The way I remember it is that a High will make my spirits high because good weather is on the way.

Last modified April 19, 2009 by Jennifer Bergman.

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