FXAK69 PAFG 082125
AFDAFG

NORTHERN ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE FAIRBANKS AK
1225 PM AKST TUE DEC 8 2009

.DISCUSSION...
THERE ARE ONLY SMALL DIFFERENCES BETWEEN THE CURRENT GFS 
AND ECMWF RUNS THROUGH FRI. THE NAM HAS SLIGHTLY HIGHER 
500 MB HEIGHTS AND 850 MB TEMPERATURES THU THROUGH FRI.

THE GENERAL TREND THROUGH FRI WILL BE FOR GRADUALLY
LOWERING 500 MB HEIGHTS AND 850 MB TEMPERATURES AS
THE UPPER RIDGE WEAKENS AND DRIFTS SLOWLY WEST. 850
MB TEMPERATURES WILL STILL BE WELL ABOVE NORMAL
OVER THE WESTERN TWO THIRDS OF THE FORECAST DOMAIN.

WINDS OVER THE WESTERN PARTS OF PKZ210 WILL CONTINUE
TO DIMINISH OVERNIGHT.

THERE CONTINUES TO BE CONSIDERABLE UNCERTAINTY IN
THE MEDIUM RANGE FORECAST. CURRENT GFS AND ECMWF RUNS
BEGIN TO DIVERGE FROM CONTINUITY BEGINNING SUN AND
DIFFER CONSIDERABLY FROM CONTINUITY BY TUE. THE GFS
ESPECIALLY HAS MUCH LOWER 500 MB HEIGHTS AND 850 MB
TEMPERATURES BY MON. THE GFS ENSEMBLE MEAN SOLUTION
IS NOT QUITE AS DRASTIC AS THE OPERATIONAL RUN. HPC
SOLUTION LEANING HEAVIER ON ENSEMBLE MEANS FROM
DAY 5 ONWARD LOOKS LIKE A GOOD PLAN AT THIS TIME.
COOLING WILL LIKELY EVENTUALLY OCCUR BUT THE TIMING
AND THE AMOUNT OF COOLING REMAINS UNCERTAIN.

COASTAL HAZARD POTENTIAL DAYS 3 AND 4...NONE

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

BRISK WIND ADVISORY FOR PKZ210.
&&

$$

RF DEC 09