Fronts2

Fronts

Warm Fronts Warm fronts occur when a warm air mass replaces a cold air mass at the surface. Since they move slowly, they often linger for days, bringing clouds and precipitation, and leaving behind warm, moist air. A warm front is symbolized by a line with semicircles facing the direction the front is moving. Cold Fronts Cold fronts occur when a cold air mass takes the place of a warm air mass at the surface. They move quickly, and bring quick thunderstorms and precipitation, leaving behind cold air. Cold fronts are symbolized by a line with triangles facing the direction the front is moving. Stationary Fronts Stationary fronts occur when a warm front and a cold front meet from opposite directions, but neither is able to move the other. These bring many days of precipitation and clouds. Stationary fronts are symbolized by a line with alternating semicircles and triangles facing opposite directions. Occluded Fronts Occluded fronts occur when a quickly-moving cold front overstakes a slower-moving warm front, and traps the warm front. At first, occluded fronts behave like cold fronts in bringing thunderstorms, but then take on the characteristic of a warm front, brining clouds and prolonged precipitation. Occluded fronts are symbolized by a line with alternating semicircles and triangles facing the same direction.