Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Northern Alaska forecast discussion 
National Weather Service Fairbanks Alaska
406 am akst sun Jan 25 2015

Synopsis...
aloft....
a long wave trough over Mainland Alaska the the northern Pacific
will persist through middle-week then cut-off over the NE Pacific at
the end of the week as ridging builds over western Alaska.
This means that the very cold temperatures now settling over
northern Alaska will persist through middle-week with some warming
towards the end of the week.

A short wave trough stretching from Barter Island to Denali will
remain stationary through 3pm sun...then move east to the alcan
border by Monday morning. Clouds and light snow are occuring east of
the trough...and will clear west of the trough.

A second trough aloft north of Barrow will move to Barrow NE by
3am Monday...to Umiat to Barter Island NE by 3pm Monday...and then move
east. Expect even colder air and some flurries with this.

850 mb...
temperatures range from -20c in the southern interior to -28c over
the Brooks range. Temperatures will cool to -30c over the eastern
interior today with little change remainder of northern Alaska.
Monday will see slight warming interior and West Coast but expect no
warming at the surface due to clear conditions.

Surface...
an Arctic cold front stretching from Mentasta Pass to Mayo will
move east today. A 990 mb low in the southern Yukon will remain in
place today then move slowly east tonight. This low is pushing
moisture back over the Arctic front causing snow in the eastern
interior. Expect another 1-2 inches of snow today east of Arctic
Village to Fairbanks to Denali. Snow will taper off from the west
this afternoon through early Monday along the previously mentioned
trough aloft.

A 1024 mb high over the Chukchi Sea will building east over
interior Alaska through Monday. This is causing a strong gradient
just northwest of the Arctic front and north winds gusting 40 miles per hour and blowing
snow through the Alaska Range passes and northwest winds gusting to 30
miles per hour in the southeast interior. These winds will decrease slightly today
and drop of more significantly tonight. Areas of clear skies and
light winds under the higher pressure will have temperatures of 15
to 30 below along the coast and 30 to 50 below in inland valleys.

A 1001 mb low 400 nm north of deadhorse will move to 300 nm north
of Demarcation Point by 3am Monday and to 200 nm east of Demarcation Point
by 3am Tuesday. This will cause west winds to increase to 25-40 miles per hour
over the Arctic coast east of Barrow through Monday with the strongest
winds in zone 204. This will keep very cold winds chills and in
zones 203 and 204 through Tuesday and could bring significant blowing
snow to zone 204. This will cause wind chill advection through Monday with
possible ground blizzard zone 204 Monday PM through Tuesday.

&&

Discussion...
models similar solutions through 3pm sun...then the NAM weakens
the low in the southern Yukon much more rapidly than the GFS and
ecmf. Favor the GFS as dynamics would not support rapid weakening
of that low as shown by the NAM solution.

&&

Afg watches/warnings/advisories...
Wind Chill Advisory for akz202-akz203-akz204-akz206-akz213.

Winter Weather Advisory for akz223-akz224.

Winter Storm Warning for akz226.

Winter Storm Watch for akz204.

Brisk Wind Advisory for pkz240-pkz245.
&&

$$

Jb Jan 15

National Weather Service Glossary of Abbreviations