Fronts and Frontal Depressions

Question 1

What is the polar front?

Answer 1

Where the polar and Ferrell air masses meet

Question 2

What does cyclogenesis mean?

Answer 2

Describes the development of a low (depression)

Question 3

What are the 6 stages of depression formation?

Answer 3

1. Stationary front
2. Frontal wave
3. Open wave
4. Mature
5. Advanced occlusion
6. Cut-off cyclone

Question 4

What is a warm front?

Answer 4

Warmer air advancing on cold air

Question 5

What is a cold front?

Answer 5

Colder air advancing on warm air

Question 6

What is an occluded front?

Answer 6

Cold front rises or undercuts the warm front

Question 7

What’s types of cloud are associated with a warm front?

Answer 7

Stratiform

Question 8

What is the slop gradient of a warm front?

Answer 8

1:150

Question 9

What is the speed of a warm front?

Answer 9

10kt

Question 10

What are the flying hazards of a warm front?

Answer 10

• FZRA in winter
• Low cloud over large areas
• Icing in cloud
• Poor visibility in rain/low cloud/frontal fog
• Aquaplaning on wet runways
• CAT around jet stream

Question 11

What happens as a warm front approaches?

Answer 11

Pressure reduces, lowering cloud with light rain

Question 12

What happens at the warm front?

Answer 12

Rain and drizzle, pressure minimum, wind veers, increase in temp

Question 13

What happens after the warm front?

Answer 13

Warm sector conditions, pressure slight increase

Question 14

What are warm sector conditions?

Answer 14

Low cloud, intermittent drizzle, poor visibility, mild temp, potential for isolated Cb

Question 15

What wind can you expect in the warm sector?

Answer 15

Geostrophic wind blowing parallel to the isobars

Question 16

What clouds would you expect at a cold front?

Answer 16

Cumulus just ahead of the front

Question 17

What is the cold front gradient?

Answer 17

1:50

Question 18

How fast does a cold front move?

Answer 18

20-30kt

Question 19

What are the flying hazards associated with cold fronts?

Answer 19

• Cb’s - turbulence, icing, lighting
• Wind shear - gust fronts and microbursts
• Poor visibility in heavy showers
• CAT around jet stream
• Aquaplaning on wet runways

Question 20

What happens as a cold front approaches?

Answer 20

Slight pressure reduction

Question 21

What happens at the cold front?

Answer 21

Heavy rain, minimum pressure, wind veers, decrease in temperature

Question 22

What happens after the cold front?

Answer 22

Pressure increase, good visibility but isolated TCu/Cu

Question 23

What weather would you find in an occluded front?

Answer 23

Combination of warm and cold sector weather

Question 24

What is a warm occlusion?

Answer 24

When the cold air behind the occlusion is warmer than the air in front of the occlusion

Question 25

What is a cold occlusion?

Answer 25

When the cold ai behind the occlusion is colder than the cold air in front of the occlusion

Question 26

How is a warm occlusion shown on a weather chart?

Answer 26

As a continuation of the warm front

Question 27

How is a cold occlusion shown on a weather chart?

Answer 27

As a continuation of the cold front

Question 28

What isa stationary front?

Answer 28

Caused by the isobars being parallel to the warm/cold air boundary

Question 29

What are the characteristics of the weather produced by a stationary front?

Answer 29

• Persists for several days

- Over a wide area