Weather Products Flashcards
What does AIRMET stand for?
Airman’s Meteorological Information
What is an AIRMET?
An AIRMET is an advisory of weather that is potentially hazardous to all aircraft but does not meet the SIGMET criteria.
How long is an AIRMET valid for?
6 Hours
What are the three types of AIRMETs?
- Tango
- Zulu
- Sierra
What is a Tango AIRMET issued for?
- Moderate Turbulence
2. Sustained surface winds of greater than 30 knots at the surface.
What is a Zulu AIRMET issued for?
- Moderate Icing
2. Freezing Levels
What is a Sierra AIRMET issued for?
- IFR Conditions (Less than 1,000’ ceiling and/or less than 3 SM visibility) affecting over 50% of the area at one time.
- Extensive Mountain Obscuration
What does CWA stand for?
Center Weather Advisory
What is a CWA?
Center Weather Advisories (CWAs) are advisories issued by the Center Weather Service Units (CWSUs) that are for conditions just below severe criteria.
What are CWAs issued for?
- Thunderstorms
- Turbulence
- Icing
- Ceiling & Visibility (IFR)
What does SIGMET stand for?
Significant Meteorological Information
What is a SIGMET?
A SIGMET advises of weather, other than convective activity, that is potentially hazardous to all aircraft.
What are SIGMETs issued for?
- Severe icing
- Severe or extreme turbulence
- Dust storms and/or sand storms lowering visibility to less than 3 miles.
- Volcanic ash
How long are SIGMETs issued for?
4 hours. The only exception is during a hurricane in which they are issued for 6 hours.
What is a convective SIGMET?
A convective SIGMET advises of weather associated with convective activity that is potentially hazardous to all aircraft.
What are convective SIGMETs issued for?
- Line of thunderstorms at least 60 miles long with thunderstorms affecting 40% of its length.
- Area of thunderstorms covering at least 40% of the area concerned and exhibiting a very strong radar reflectivity or a significant satellite or lightning signature.
- Embedded or severe thunderstorms expected to occur for more than 30 minutes.
What are some special issuance criteria for a convective SIGMET?
- Tornado
- Hail greater than or equal to 3/4 inches in diameter
- Wind gusts greater than or equal to 50 knots
How often are convective SIGMETs issued and how long do they last?
Issued hourly at Hour+55. The text of the bulletin consists of either an observation and a forecast or just a forecast. The forecast is valid for up to 2 hours.
What does METAR stand for?
Meteorological Aviation Report
How often are METARs released?
Hourly
Is the wind direction in a METAR in reference to true or magnetic north?
True North. Remember, if you read it, it must be true.
Decode this METAR:
KPSC 211753Z 36008KT 10SM CLR 26/09 A3002 RMK AO2 SLP162 T02610089
- KPSC - Tri-Cities Airport
- 211753Z - This report was released on the 21st of the month at 17:53 UTC.
- 36008KT - The wind is coming from 360 (N) @ 8 knots.
- 10SM - 10 statute miles of visibility.
- CLR - Sky conditions CLEAR
- 26/09 - Temperature 26 Celsius / Dewpoint 9 Celsius.
- A3002 - Altimeter setting 30.02” Hg.
- RMK - Remark Section
- AO2 - Sensor with precipitation discrimination ability.
- SLP162 - Sea level pressure 1162 millibars
- T02610089 - Temperature: 26.1 / Dewpoint: 8.9
What does TAF stand for?
Terminal Aerodrome Forecast
How long are TAF’s valid for?
Usually 24 hours, sometimes 30.