What Is a Trowel in Meteorology

@DeltaLima: A trowal is a thin occlusion of warm air ahead of a cold front meeting cool air. In that small warm atmospheric valley the aft cold front and the warm front ahead are very close. Further ahead of the trowal there is a high risk of icing, due to rain falling from the trowal thru a mass of cool air.

How does a Trowal form?

When the low is at its maximum intensity it is an Occluded Front, and as the fronts collide more it becomes a TROWAL, as the cold air under cuts the warm front and forces it aloft.

What does occluded mean in weather?

In meteorology, an occluded front is a weather front formed during cyclogenesis. The classical view of an occluded front is that it initiates when a cold front overtakes a warm front, such that the warm air is separated (occluded) from the cyclone center at the surface.