What is the difference between a Low pressure and a High pressure system?

There are two physical differences between Low pressure systems and High pressure systems.

First, is the circulation surrounding them.

Secondly, is the atmospheric motion that they cause.

Low pressure systems circulate counter-clockwise.

High pressure systems circulate clockwise.

These "motions" (caused by these circulations) are the building blocks in our atmosphere. They give us our weather.

A Low?s counter-clockwise circulation forces air upward (ultimately resulting in condensation, cloud formation and ultimately precipitation).

A High?s clockwise circulation causes a sinking motion in the atmosphere, resulting in fair/clearer and often sunnier skies.

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Current 38°F 24°F
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Record 61°F January 19, 1915 -11°F January 19, 1994