Met Flashcards
- What is FG, BR, GR, FU, VC, BC?
a. FG - -Fog
BR – Mist
GR – Hail
FU – Smoke
VC – In the vicinity
BC – Patches
Write out answers, not multi choice
Definition of CAVOK:
Ceiling and Visibility OK, for international use. It indicates that:
No clouds exist below 5,000 feet or below the highest minimum sector altitude, whichever is greater, and no cumulonimbus are present.
Visibility is 10 kilometres or more and,
No precipitation, thunderstorms, sandstorm, dust storm, shallow fog, or low drifting dust, sand or snow is occurring.
- What type of cloud type would give severe icing?
a. Cumuliform, Cumulonimbus, Nimbostratus, (severe)
- Which cloud type would give +RA?
b. NS
- Rain is striking the aircraft and freezing on impact why?
a. The air is supercooled, and freezes on impact with the aircraft.
- Datum for METAR
b. True and AAL
- How long is a TEMPO valid?
a. When used in a TAF, means “forecast temporary which reach or pass specified values and last for a period of less than one hour in each instance and, in the aggregate, cover less than one-half of the period during which the fluctuations are forecast to occur”
When used in a TREND, means “forecast temporary fluctuations which reach or pass specified threshold values and last for a period of less than one hour in each instance. Such fluctuations are expected to occur during the 2 hours following the issue time of the METAR, SPECI or METAR AUTO, and to take place sufficiently infrequently for the prevailing conditions to remain those originally reported in the METAR, SPECI or METAR AUTO:”
- What is TREND
a. A TREND is an abbreviated forecast appended to a METAR or SPECI from Whenuapai or Ohakea. TRENDs provide an indication of any expected changes to those reported in a METAR or SPECI. Only the elements expected to change are included.
b. The period of a landing TREND is two hours
- You observe an altimeter of an aircraft parked at an aerodrome when a cold front passes. What will you see?
a. Increase pressure/altitude then decrease
- What is an occluded front?
a. A cold front moving faster than a warm front, and catches up. This is now called an occluded front. The system will end up decaying when the air in the warm sector has been lifted so high, there is little energy available from the release of latent heat.
- What weather conditions categorise a stationary front?
a. In situations where advancing cold air is directly and equally opposed by advancing warm air, a stationary front will form.
Shown on map by front with triangles pointing to warm air side, opposed by half-rounds pointing into the cold air side.
Generally speaking, stationary fronts are weak and often represent the remains of a decaying frontal system. Thus, not a great deal of cloud, wind or weather associated with them.
- What is a katabatic wind?
a. A wind that travels down a valley wall, due to the cooling of the wall, becoming more dense air and sinking.
Greatest on north/south orientated valleys, radiation cooling is enhanced whenever terrestrial radiation is freely allowed to escape.
- Tropopause is higher/lower and warmer/colder at poles than equator.
a. Is higher over the equator 60,000 ft (18km, and 8km over poles), and about -80°C (over the poles in summer is about -47°C)
- Dew point definition?
a. The dew point is the temperature at which a parcel of air saturates under a constant pressure.
