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Stationary Fronts - Windows to the Universe

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Weather map showing a stationary front
Windows to the Universe image by Lisa Gardiner

# Stationary Fronts

A stationary front forms when a cold front or warm front stops moving. This happens when two masses of air are pushing against each other but neither is powerful enough to move the other.

A stationary front may stay put for days.  The front may start moving again, becoming either a cold or warm front. Or it may break apart.

Air temperature and wind can be different on opposite sides of a stationary front. The weather is often cloudy along a stationary front and rain or snow often falls, especially if the front is in an area of low atmospheric pressure.

On a weather map, a stationary front is shown as alternating red half circles and blue triangles like in the map at the left.

#### Shop Windows to the Universe Science Store!

Cool It! is the new card game from the Union of Concerned Scientists that teaches kids about the choices we have when it comes to climate change—and how policy and technology decisions made today will matter. Cool It! is available in our online store.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support!