Weather Flashcards
Stable Air
Stratoform clouds, smooth air, poor visibility, and steady precipitation.
unstable Air
Cumuliform Clouds, more turbulence, showery precipitation, good visibility.
what are windshears
sudden change in windspeed/direction over a short distance.
Mountainwave wind
Air is pushed up a mountain, meets inversion, and is redirected toward the ground.
isobars close together
indicates strong wind
standard conditions
29.92 In. mercury and 15 Degrees celsius. Temp decrease by 2 degrees for every 1000 ft gained.
how do clouds form
air condenses into visible moisture. meeting point of dewpoint and temp.
thunderstorms
form with rising force, unstable air, sufficient water vapor.
t-storm stages
cumulus, mature, dissapating.
microbursts
localized column of sinking air caused by evaporating air from precipitation.
how does icing form
freezing conditions and visable moisture
types of icing
clear ice (heavy, glossy) Rime (rough, milky) Mixed (combination of the two)
types of fog
Radiation (ground cools air), Advection (warm air moves over cool ground [water]) Frontal (warm air runs over cool front), upslope (warm air hits mountain and cools as it rises), Steam (evaporation creates fog)
personal weather minimums
No more than gusting 20 knots, no less than 5 miles visibility.
how could you get weather info in flight?
call flight service station,
(122.2, 122.4, 122.6) AWOS/ATIS, foreflight, ADSB.
How long is a TAF valid?
Check start/end times on forecast
Winds aloft 9900?
Light and variable
How often are convective sigmets issued?
Every hour
How do low pressure systems move?
Inward, Upward, and Counterclockwise
How do high pressure systems move?
Outward, downward, and clockwise
What is a trough?
And elongated area of relatively low pressure
What is a ridge?
Elongated area of relatively high pressure
What is an isobar?
Isobars are lines on a chart that connect areas of identical or constant barometric pressure
What causes winds to flow parallel to isobars
Coriolis effect
