Weather Flashcards
What are the different types of frontal systems?
Cold Front-Acts as a snow plow due to the dense air, typically involves rain or haze due to the fast forming clouds, usually associated with cumulus clouds
Warm Front-Fog can be expected to form along the front, generally poor vis, stable pressure
Stationary Front-When 2 air masses meet and neither is overtaking the other.
Occluded Front- Cold air mass catches up to a warm air mass and displaces it from underneath, very poor weather and storms can typically be associated with this front.
3 stages of a thunderstorm?
Cumulus-updrafts
Mature-When rain starts
Dissipating-downdrafts
Types of icing
Clear-hard and glossy, slow forming
Rime-brittle and frost like, fast forming
Mixed
Types of Fog
Ground (Radiation)- Cool humid air over cool ground (no wind) ground cools air to dew point
Advection- Moist air moves over cold ground or water (wind no stronger than 15kts)
Upslope- Temp cools as air rises and meets dew point
Precipitation induced fog- Warm rain falling through cold air, evaporation from rain saturates cool air and forms fog
Ice fog- Temp below freezing, water vapor freezes
Airmet
Moderate turbulence and icing, surface winds of 30kts or greater, widespread restricted visibility covering 3000sq miles
Valid for 6 hours
Tango: light-moderate turbulence with surface winds 30kts or greater
Sierra: ceilings less than 1000 or visibility less than 3sm effecting over 50% of the area
Zulu: light-moderate icing
Sigmet
Severe or greater turbulence, icing, or IMC due to volcanic ash, sand, or dust. Must cover 3000sq miles
As needed and valid for up to 4 hours, or 6 for hurricanes
Convective Sigmet
Embedded TS or squall lines effecting 40% or greater of a 3000sq mile area.
Surface winds greater than or equal to 50kts, hail 3/4” or larger.
Valid for 2 hours, issued hourly 55 minutes past the hour.
TAF
Issued every 6 hours, generally apply for 24-30 hours within 5nm of reporting airport.
