This causes a warm occluded front to act more like a warm front instead. A warm front is known for producing lighter rains that do not have the severe symptoms of the storms produced by cold fronts. The rain is often steady and covers a wide area of land. Winds do not change direction and the air temperature remains consistent.
An occluded front is not a very common occurrence. To create an occluded front, an existing warm or cold front must catch up with another front ahead of it on the weather map.
When the two fronts combine, the colder air is pushed beneath the warmer air, resulting in an occluded front that is either characterized as warm or cold, depending on the direction of the occlusion.
These fronts are symbolized on a weather map by a purple line with both semicircles and triangles on it. On colored weather maps, an occluded front is drawn with a solid purple line. Changes in temperature, dew point temperature, and wind direction can occur with the passage of an occluded front. In the map below, temperatures ahead east of the front were reported in the low 40's while temperatures behind west of the front were in the 20's and 30's.
The lower dew point temperatures behind the front indicate the presence of drier air. Warm front- a front in which warm air replaces cooler air at the surface. Some of the characteristics of warm fronts include the following: The slope of a typical warm front is more gentle than cold fronts. Warm fronts tend to move slowly. Warm fronts are typically less violent than cold fronts. Although they can trigger thunderstorms, warm fronts are more likely to be associated with large regions of gentle ascent stratiform clouds and light to moderate continuous rain.
Warm fronts are usually preceded by cirrus first km ahead , then altostratus or altocumulus km ahead , then stratus and possibly fog. Behind the warm front, skies are relatively clear but change gradually. Warm fronts are associated with a frontal inversion warm air overrunning cooler air. If a warm front exists on a weather map, it will be northeast of the cold front and often, to the east of a surface low pressure area.
Clouds and precipitation are quite prevalent to the north of the warm front. In Oklahoma, warm fronts are rare in the winter and non-existent in the summer. Stationary front- a front that does not move or barely moves. Warm fronts often form on the east side of low-pressure systems where warmer air from the south is pushed north.
You will often see high clouds like cirrus, cirrostratus, and middle clouds like altostratus ahead of a warm front. These clouds form in the warm air that is high above the cool air. As the front passes over an area, the clouds become lower, and rain is likely.
There can be thunderstorms around the warm front if the air is unstable. On weather maps, the surface location of a warm front is represented by a solid red line with red, filled-in semicircles along it, like in the map on the right B.
The semicircles indicate the direction that the front is moving. They are on the side of the line where the front is moving. Notice on the map that temperatures at ground level are cooler in front of the front than behind it.
A stationary front is represented on a map by triangles pointing in one direction and semicircles pointed in the other direction.
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.
Winds blowing parallel to the front instead of perpendicular can help it stay in place. A stationary front may stay put for days. If the wind direction changes, the front will start moving again, becoming either a cold or warm front. Or the front may break apart. Because a stationary front marks the boundary between two air masses, there are often differences in air temperature and wind on opposite sides of it.
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