Chapter 17 (PPT)

Question 1

Where do ‘Foehn’ Downslope Winds occur?

Answer 1

Alps

Question 2

What is the temperature of ‘Foehn’ Winds?

Answer 2

Warm

Question 3

Where do ‘Bora’ Downslope Winds Occur?

Answer 3

Adriatic Sea

Question 4

What is the temperature of ‘Bora’ Winds?

Answer 4

Cold

Question 5

Where do ‘Chinook’ Downslope Winds Occur?

Answer 5

Rocky Mountains

Question 6

What is the temperature of chinook winds?

Answer 6

Warm

Question 7

Where do ‘Santa Ana’ Downslope Winds occur?

Answer 7

Southern California

Question 8

What is the temperature of ‘Santa Ana’ winds?

Answer 8

Warm

Question 9

Where do ‘Katabatic’ Downslope winds occur?

Answer 9

Antarctica and Greenland

Question 10

What is the temperature of ‘Katabatic’ winds?

Answer 10

Cold

Question 11

what are the 5 Downslope winds?

Answer 11

• Foehn
• Bora
• Chinook
• Santa Ana
• Katabatic

Question 12

For foehn downslope winds, would the new airmass be colder or warmer than the one it replaced?

Answer 12

Will be warmer than the airmass replaced

Question 13

For Bora downslope winds, would the new airmass be cooler, or warmer?

Answer 13

Will be cooler that the airmass replaced

Question 14

What are Mountain Waves?

Answer 14

When a large scale weather patterns produce a strong, deep flow of air across the Rockies, The peaks act like Rocks in a stream bed.

Question 15

Windward side?

Answer 15

Upwind side of mountain range

Question 16

Leeward side?

Answer 16

Downwind side of a mountain range.

Question 17

Lee Waves?

Answer 17

A series of waves in the flow downstream from a mountain

Question 18

Are Lee waves visible?

Answer 18

No, they are invisible

Question 19

What types of clouds form in Lee Waves?

Answer 19

Lenticular Clouds. (Visible)

Question 20

The Hydraulic Jump?

Answer 20

Marks the transition from strong winds upstream of the jump to weaker surface winds downstream of the jump.

Question 21

What 3 factors determine the temperature of air in downslope windstorms?

Answer 21

• Upstream Air
• Latent Heat corresponding to amount of precipitation falling out of chinook cloud wall
• Adiabatic Warming During Descent

Question 22

What 3 weather features are required for a chinook to form?

Answer 22

• A stable layer (inversion) about 1-2 km above mountaintop
• Strong Surface pressure gradient across mountains (From east to West)
• Strong, Westerly winds at ~700mb (about mtn top)

Question 23

Lee trough?

Answer 23

An area of low pressure on the lee side of the mountains

Question 24

How does the sea level pressure change from west to east across colorado?

Answer 24

It decreases quite a bit

Question 25

How do the temperatures along the colorado front range compare to the temperatures further east?

Answer 25

Much Warmer

Question 26

Santa Ana Winds?

Answer 26

The name given to downslope windstorms in Southern California

Question 27

What weather conditions are required for Santa Ana winds to form?

Answer 27

- Strong high pressure over great basin - Strong North-South pressure gradient over southern California - An inversion layer above mountaintop level may also be needed

Question 28

How do Santa Ana winds compare to chinook winds in colorado?

Answer 28

Winds are easterly, and also less extreme than chinook winds

Question 29

When do the strongest Santa Ana winds typically occur?

Answer 29

Late fall and winter (When grass/brush is quite dry)

Question 30

What hazards are associated with Santa Ana Winds?

Answer 30

Fires, and resultant smoke/pollution

Question 31

How often do Santa Ana winds occur?

Answer 31

!20 times per year, lasting 36 hrs on average.

Question 32

Katabatic Wind?

Answer 32

A cold, downslope wind that is the result of cold air flowing downslope under the force of gravity.

Question 33

How do Katabatic Winds Form?

Answer 33

Simply from having a dense pocket of cold air dorm ar high elevations, which spills over the edge and rushes towards the surface.

Question 34

How do Katabatic Winds Differ from the downslope windstorms discussed above?

Answer 34

There are largely a density effect, where as chinooks etc. are a dynamic, mountain wave effect.

Question 35

Where are katabatic winds most likely to occur?

Answer 35

Antarctica, Greenland and Patagonia

Question 36

What weather conditions are associated with strong katabatic winds?

Answer 36

Blowing snow, very cold and abrupt winds