Storm front over Lake Superior (US)
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Courtesy of EPA

Weather Fronts

Weather fronts can cause clouds, rain, thunderstorms, gusty winds, and even tornadoes. Usually the skies clear once the front has passed.

Weather fronts happen because not all air is the same. In some places, air is warm and humid. In other places air is cool and dry.  A weather front is where two different types of air meet.

Often the air is unsettled at a front. This can cause clouds and storms. Some fronts do not cause weather events, just a change in temperature. A few fronts that form in the tropics can develop into tropical storms or hurricanes.

Fronts move over time as the air moves. The direction that fronts move is often guided by high winds. Mountains can change the direction that a front is moving.

There are 4 different types of fronts: cold fronts, warm fronts, stationary fronts, and occluded fronts.

Last modified August 12, 2009 by Lisa Gardiner.

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