16. Thunderstorms and Turbulence Flashcards
Cumulonimbus mamma clouds are associated with
Violent thunderstorms and tornadoes.
Cellular pouches hanging beneath the cloud.
Nimbus = rain
The mature stage of a thunderstorm begins with ?
Start of precip
Which stage of tstorm is associated with downdrafts?
Dissipating
T storms which produce the most hazard are?
Squall line Tstorms.
Squall = non frontal narrow band.
Develops ahead of a cold front in moist unstable air.
Conditions necessary to form cumulonimbus clouds are?
Lifting action & unstable moist air
2 Characteristics of moist unstable air mass?
Cumuliform clouds and showery precip.
What clouds have the greatest turbulence?
Cumulonimbus
Towering Cumulus
Nimbostratus
Cumulonimbus
Seen on sunny afternoons.
Turbulence in and below cloud.
Smooth above cloud
Towering cumulous height > Cumulonimbus
Weather feature concerning to pilot among a cold front?
Thunderstorms and heavy rain
When flying over mtn ranges the greatest potential for danger from turbulent air currents will usually be encountered
On leeward side flying into the wind.
Flying into wind means flying toward mountain where sink can occur.
What is base of cumulus cloud if temp = 70 and dewpoint is 48?
70 - 48 = 22
22 / (4.4 F / 1000’) = 5000
If there is thunderstorm activity near airport you want to land at, what hazardous phenomenon might be expected?
Wind shear turbulence
What cloud types would indicate convective turbulence?
Cirrus, nimbo stratus, towering cumulus
Towerng cumulus
When may low level wind shear be expected?
Passing frontal systems
t storms
inversions
strong upper level winds
T storms reach their greatest intensity in what stage?
Mature
What weather phenomenon is always associated with a t storm?
Lightning
What feature is usually associated with the cumulus stage of a t storm?
Continuous updraft
K-Index is an indication of
Probability of a t storm
15 = 0% > 40 = 100%
Low level turbulence and icing can become hazardous in
upslope fog, rain induced fog, steam fog
Steam fog (sea smoke)
Cold dry air over warm waters
If an unstable air mass is pushed upward what type of cloud can be expected
Clouds with considerable vertical development and associated turbulence. Cumulus
What is considered to be the most hazardous condition when soaring close to a t storm
Wind shear and turbulence
A non-frontal narrow band of active t storms that develops in front of a cold front is?
Squall line
When encountering severe turbulence you should
Maintain a constant attitude
