An occluded front forms when what happens?

An occluded front forms when what happens?

• A. Warm front overtakes cold front
• B. Cold front overtakes warm front
• C. Front remains stationary
• D. Cold front separates from warm front

Answer: (B)

Occlusion occurs when the cold front overtakes the warm front. The air behind the cold front is denser and typically moves faster than the air ahead of the warm front, so the advancing cold front catches up and lifts the warm air off the surface. This wedging of warm air aloft creates a single front aloft—the occluded front. If the warm front were to overtake the cold front, or if the front stayed stationary or separated, you wouldn’t form an occlusion in the same way.

Occlusion occurs when the cold front overtakes the warm front. The air behind the cold front is denser and typically moves faster than the air ahead of the warm front, so the advancing cold front catches up and lifts the warm air off the surface. This wedging of warm air aloft creates a single front aloft—the occluded front. If the warm front were to overtake the cold front, or if the front stayed stationary or separated, you wouldn’t form an occlusion in the same way.