Area Forecast Discussion
Issued by NWS Fairbanks, AK
FXAK69 PAFG 102329
Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
229 PM AKST Sat Dec 10 2016
A 555dm high centered over the North Slope will move south to a
center over Tanana by 3pm Sun...then retreat south over the Gulf
of Alaska Mon and then rebuild over mainland Alaska from Tue into
Wed. Conditions will remain generally clear over Northern Alaska
through Mon under the high with very strong inversions allowing
calm valleys to remain very cold while windy areas and hills will
see temperatures above zero.
These conditions will change on the West Coast Sun night and Mon
as as short wave moves north bringing snow and warmer temperatures
to the West Coast Sun night and Mon...and warmer temperatures with
a chance of snow to the Western Interior Mon night and Tue.
Several strong short waves moving north over the Bering Sea
late next week will bring several strong storms with them which
could bring storm force winds to the Bering Sea and West Coast
late next week.
A short wave trough in the Bristol Bay will move to Western Norton
Sound by 3pm Sun...to the southern Chukchi Sea Mon. Expect a
chance of snow with this trough.
A 1044 mb high over the Alcan Border with a ridge extending west
along the Brooks range and over the Chukchi Sea will weaken very
slowly through Mon and then more rapidly through Tue. Conditions
will be generally clear under this ridge with cold air pooling in
valleys and temperatures warming above zero F over hills.
The high will cause the Tanana Valley Jet to continue to blow
through Sun and then gradually weaken through Mon.
An arctic warm front stretching from the Beaufort Sea to the SE
Interior has brought alto stratus clouds to the eastern Interior
today. This area of clouds is now thinning and is expected to be
scattered by 6pm and dissipated by 9pm.
This front will move to Northway northeast by 3am Sat and could
bring some more clouds to the Alcan Border area tonight but no
clouds are expected to develop to the west.
An Arctic cold front moving into the Chukchi Sea on Sun night will move
east to lie just north of the Arctic Coast of Alaska by 3pm Mon.
Expect this to bring some fog and flurries to the Arctic Coast
Mon along with west winds.
An occluded front moving north into the central Bering Sea Sun
night will move to the northern Bering Sea Mon...Weaken along the
West Coast Mon Night and then dissipate over the western Interior
Tue. This will bring snow into zone 213 late Sun night and to the
Capes of the West Coast by 3pm Mon. Expect SE winds 25 kt with
along and just ahead of this front with gusts to 35 kt. Right now
it looks like 1-3 inches of snow with this front with temperatures
warming to near freezing with the front. Since snow will be wet
and winds are generally less than 35 kt do not expect Blizzard
conditions Sun Night or Mon. This could be Blowing snow advisory...
but this is starting late in the 3rd period so we will hold off
on issuing anything until we have more certainty on this feature.
A very strong low moving into the Southern Bering Sea Mon night
and Tue will bring southeasterly Gale force winds to the Northern
Bering Sea Tue. This will bring another chance of snow with rain
possible to St Lawrence Island on Tue.
Models initialize well at 500 mb and show similar solutions through
3pm Mon. There are slight differences in details of the timing and
strength of short waves Mon night through Tue...but the
differences get larger by the end of next week. ECMF brings the
second round of precipitation into St Lawrence Island on Mon more
quickly than the GFS. At this time we will go with the GFS through
Sun and then use the ECMF to bring preciptiation in the the West
Coast on Mon and Tue more quickly than the GFS. Will use ensembles
later next week due to widening differences in the models.
At 18Z Sat models initialize 4-6 mb too weak on the high pressure
stretching from the the Alcan Border west across the Brooks Range
into the Chukchi Sea. Expect pressure to remain higher than models
indicate through Sun which will result in easterly drainage winds
down the Tanana Valley to remain stronger than models indicate.
Again will use the GFS through Sun and then merge to the ECMF Mon
and Tue which brings the weather front northward more quickly over
the West Coast.
Coastal Hazard Potential Days 3 and 4...None.
Heavy Freezing Spray Warning for PKZ210.
JB DEC 16