Mountain Wave Presentation

Question 1

Mountain Wave definition

Answer 1

Oscillations on the lee side (downwind) of a mountain caused by the disturbances in the horizontal airflow due to the impeding terrain

Question 2

Windward means?

Answer 2

Windward is the direction upwind from the point of reference, alternatively the direction from which the wind is coming

Question 3

Lee side

Answer 3

Leeward is the direction downwind from the point of reference

Question 4

Formation of a mountain wave

Answer 4

Wind direction30degrees perpendicular to the mountains

Wind velocity windward side 25 kt or more

Winds also increased with height

Stable air mass layer aloft or isothermal layer

Question 5

Crest means

Answer 5

Top of the mountain

Question 6

Wavelength

Answer 6

Distance from crest to crest

Question 7

Average wavelength is

Answer 7

8 NM

Question 8

Average total wave distance from mountain top to final dissipation is?

Answer 8

150 NM

Question 9

Amplitude

Answer 9

Is half the vertical distance from the wave trough to crest

Question 10

What is GFA

Answer 10

Graphic Atea Forcast

Question 11

When are these formed Orographic clouds

Answer 11

These are formed when air is forced to rise by the earths topography

Question 12

Lenticular clouds ?(2)

Answer 12

They form in the crest of the waves can be very high and hundreds of miles long

As the air in a mountain wave rises it cools by expansion and condenses out moisture to form the leading edge of the lenticular cloud

Occurs from 20000 to 40000

Question 13

Lenticular clouds will be reported as ??

Answer 13

ACSL alto cumulus standing lenticular

CCSL cirro cumulus standing lenticular

Question 14

What’s is lenticular clouds

Answer 14

Are a visual indicator of mountain waves

Question 15

Roll/Rotor clouds are?

Answer 15

Another indicator of the presence of mountain waves

They posses the greates amounts of turbulence

Avoid flying through , between or below them

Question 16

When roll/rotor clouds will be form

Answer 16

Downwind from each wave crest and within the lower turbulent zone.

Question 17

Cap clouds?

Answer 17

These lie over the top of the mountain and they will extend partially down the leeward slopes

Indicate an extremely strong downdraft

Question 18

Anabatic winds are?

Answer 18

Are form as the sunward side of a mountain slope heats up