What is the difference between a trough and a trowel?
Trough: elongated areas of (L) - cloudy and rainy
Trowel: Trough of Warm Air Aloft (Trowal) results from Occluded Fronts
What do isobars signify?
Lines connecting points of equal atmospheric pressure measured in 4 hpa increments. Closer the bars the more wind / turbulence.
What are the GFA issue times?
0000, 0600, 1200, 1800 Z
What weather does an LWIS give you?
- Temperature
- Wind
- Altitude
- Dewpoint
What weather does an AWOS give you?
- LWIS +
- Sky
- Clouds
- Icing
- Precipitation
- Visibility
How many sky conditions are there and what are they?
- VV: Vertical visibility when sky is obscured
- SKC: Sky clear - no cloud present
- CLR: Clear below 10,000’ as interpreted by AWOS
- FEW: 0 to 2/8 (oktas) summation amount of cloud
- SCT: Scattered - 3/8 to 4/8 of sky is covered
- BKN: Broken - 5/8 to 7/8 of sky is covered
- OVC: Overcast - 8/8 of sky is covered
What are the percentages for convective clouds and showers?
- ISOLD: <= 25%
- OCNL: 26-50%
- FRQ: >50%
What are the percentages for non-convective clouds, precipitation, icing, and turbulence?
- LCL: <= 25%
- PTCHY: 26-50%
- XTNSV: >50%
What weather minimums are used for an alternate with a TEMP forecast?
The weather during the TEMP period
What weather minimums are used for an alternate with a BCMG forecast?
- Beginning of time period when weather is getting worse
- End of time period when weather is getting better
What does a PROB30 weather forecast impact?
- Landings
- Minimums are per the plate
