And occluded front is usually caused by ______?

And occluded front is usually caused by ______?

• A. A warm front overtaking a cold front
• B. A cold front overtaking a warm front
• C. A stationary front merging with a warm front
• D. A dry line boundary

Answer: (B)

Occluded fronts form in mid-latitude cyclones when a cold front catches up to and overtakes a warm front. The cold front is typically faster and denser, so as it closes in, the warm air ahead of the warm front is lifted upward off the surface. When the cold front overtakes, it undercuts the warm front, and the boundary becomes an occluded front with the warm air aloft. This setup often brings lift and precipitation around the occlusion and a drop in surface temperature behind the front. The other scenarios don’t produce the classic occlusion mechanism: a warm front overtaking a cold front isn’t how occlusions typically form, a stationary front merging with a warm front isn’t the standard process, and a dry line is a different kind of boundary.

Occluded fronts form in mid-latitude cyclones when a cold front catches up to and overtakes a warm front. The cold front is typically faster and denser, so as it closes in, the warm air ahead of the warm front is lifted upward off the surface. When the cold front overtakes, it undercuts the warm front, and the boundary becomes an occluded front with the warm air aloft. This setup often brings lift and precipitation around the occlusion and a drop in surface temperature behind the front. The other scenarios don’t produce the classic occlusion mechanism: a warm front overtaking a cold front isn’t how occlusions typically form, a stationary front merging with a warm front isn’t the standard process, and a dry line is a different kind of boundary.