Strange TAF
Thread Starter
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From: EuroGA.org
Strange TAF
LGIR 210400Z 211212
32012KT 9999 FEW020 SCT030
PROB30 TEMPO 0006 7000 RA SCT020 BKN030
PROB30 TEMPO 0006 5000 TSRA SCT012 FEW018CB BKN025=
Both PROB30 TEMPO are for the same time period: 0000-0600.
32012KT 9999 FEW020 SCT030
PROB30 TEMPO 0006 7000 RA SCT020 BKN030
PROB30 TEMPO 0006 5000 TSRA SCT012 FEW018CB BKN025=
Both PROB30 TEMPO are for the same time period: 0000-0600.
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From: He's on the limb to nowhere
Yep, PROB10 isn't allowed, only 30 or 40.
Weather is all probablilty. Normally you show the most probable forecast (with significant changes within the period). If there are two PROBs the same, which would you show?
Weather is all probablilty. Normally you show the most probable forecast (with significant changes within the period). If there are two PROBs the same, which would you show?
Thread Starter
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From: EuroGA.org
Why didn't the forecaster just list every possible weather? 
Maybe I don't get out enough but in 5 yrs and 700hrs I have not (to my recollection) seen a dual-possibility TAF like that. And I do fly abroad.
Maybe I don't get out enough but in 5 yrs and 700hrs I have not (to my recollection) seen a dual-possibility TAF like that. And I do fly abroad.
Gizajob
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From: uk
A bit unusual I agree but perfectly understandable in my head anyway!:
Between midnight and six a.m., 30% probability of temporary periods of rain etc and 30% probability of some charlie bangers at the same time.
Between midnight and six a.m., 30% probability of temporary periods of rain etc and 30% probability of some charlie bangers at the same time.
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From: He's on the limb to nowhere
At least that way they would get it right! They just list the most probable, which is probably why they get it wrong so often. Even so, looking at that TAF, the TS might make you stay away whereas just the RA might make you head out. If the RA one was a PROB40 you wouldn't get the PROB30 TSRA. Some might say that was important to know.
Good reason to keep an ear on the weather if on a long trip, the idea is that they get more accurate the closer to the time you arrive.
Good reason to keep an ear on the weather if on a long trip, the idea is that they get more accurate the closer to the time you arrive.
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From: Grand Com f'Ort
This forecaster chose to detail both. PROB 10 is not 'not allowed'; it's not ICAO SARP, but an ICAO-contracted State could file a difference.
TightYorksherMan
Joined: May 2002
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From: Peak District
Quote:
PROB 10 is not 'not allowed'; it's not ICAO SARP, but an ICAO-contracted State could file a difference.
Jeez ...
FF
PROB 10 is not 'not allowed'; it's not ICAO SARP, but an ICAO-contracted State could file a difference.
Jeez ...
FF
Joined: Mar 2002
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From: Euroland
Between Midnight and 6AM there will be showers of rain. Some of those showers may affect the airfield at times and some of those showers will be heavy with thunder.
Seems very simple and logical to me.
Regards,
DFC
