Trowal/Occluded Front

Question 1

What does Trowal stand for?

Answer 1

Trough of Warm Air Aloft

Question 2

What is an occlusion/trowal?

Answer 2

Cold air that ‘catches up’ to warm and pushes the warm air up

Question 3

How is a trowal depicted on a map vs an occlusion?

Answer 3

Twowal is a blue line with little red dashes
Occlusion is blue spikes and red bubbles together and pointing in the same direction. They are the same thing, trowal is Canadian

Question 4

How many air masses are involved in the creation of a trowal?

Answer 4

Three. Warm, cool (partially mixed), and cold

Question 5

What kind of weather can be found at a trowal/occluded front and where will that weather typically be found?

Answer 5

• Generally weather at a trowal resembles that of both cold and warm fronts
• The clouds ahead of the trowal will be similar to those found ahead of warm fronts. Clouds behind the trowal will be like those found just behind a cold front
• But Clouds and precip really depend on the moisture content of the warm air and can vary from dry, to showery, to heavy precip
• Weather in a trowal will generally be found in the northeast sector.

Question 6

Diagram of a trowal/occlusion

Answer 6

Question 7

Another diagram of an occluded front/trowal

Answer 7