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A cold front is diagrammed as spikes pointing to its direction of travel. A warm front is shown as semi-circles in a traditional weather map, also pointing to its direction of travel. An occluded front is a combination of those two signs: they are indicated on a weather map either by a purple line
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is significant along the cold front. Small isolated occluded fronts often remain for a period after a low-pressure system has decayed and disappeared and these create cloudy conditions with patchy areas of rain or showers.
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A wide variety of weather can be found along an occluded front, with heavy thunderstorms and tornadoes possible, but usually, their passage is instead associated with a drying of the air mass. Additionally, cold core
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with alternating semicircles and triangles pointing to the direction of travel, or by red semicircles and blue triangles pointing to the direction of travel. On the other hand, a TROWAL is diagrammed on
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is often offset from the range of the associated weather which occurs at the TROWAL. The TROWAL, is primarily found with a connection to the warm occlusion, and are rarely seen in cold occlusion.
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oft), is the estimated projection of the wedge of warm air above the surface, and is at the same position in both cases. Consequently, the location of the occluded front appearing in the
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However, the clouds and precipitation are not really the location where the projection on the Earth's surface of the occluded front is, but it is with the TROWAL position.
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The occluded front symbol should show where the cold air intersects the surface. It thus varies between warm and cold occlusions. The TROWAL (short for
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One symbol of an occluded front is the TROWAL symbol with alternating blue and red lines similar to a cold/warm front junction
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maps by the junction of blue and red lines like the junction of cold and warm fronts aloft.
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center at the surface. The point where the warm front becomes the occluded front is the
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Diagram of a cyclone in the early stages of occlusion in the
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Occluded fronts and the occlusion process: A fresh look at conventional wisdom.
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Occlusion principle with positions of warm/cold occlusion fronts and the trowal
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39:. The classical and usual view of an occluded front is that it starts when a
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near a cyclone, such that the warm air is separated (occluded) from the
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Meteorological interaction of warm and cool air masses
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and rotation around the cyclone as the cyclone forms.
205:Bull. Amer. Meteor. Soc., 92, 443–466, ES19–ES20.
216:AIR MASSES AND FRONTS - THE OCCLUDED FRONT (1962)
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91:Occluded fronts usually form around mature
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59:that develops at this point is called a
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201:Schultz, D. M., and G. Vaughan, 2011:
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186:Stationary front
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