Brisk Wind Advisory 62, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
1046 AM AKST Mon Feb 6 2017

.DISCUSSION...
The 12z model suite initialized well against the 12z analysis and
verified well against the 18z analysis. Model spread is minimal in
the short range and reasonable in the mid range. Model spread both
from run to run and between model families is considerable in the
long range.

Aloft at 500 hpa, a 528 DAM low over western alaska will continue
to drift to the south to be located 100 NM north of Nunivak
Island Tuesday and will remain nearly stationary through Wednesday
as a very cold low complex moves south out of the high arctic and
develops a cold long wave trough along a Demarcation Point to
Kodiak Island line by Thursday morning. The cold long wave trough
will remain over northern Alaska through the weekend. 850 mb
temperatures over Fairbanks will drop from around 2 below this
morning to around 5 below Tuesday morning and to around 10 below
by Wednesday morning. The cold airmass begins to move over
Fairbanks on Thursday with 850 mb temperatures dropping to around
15 to 20 below and to 25 to 30 below celsius Friday, Saturday and
Sunday. 850 mb temperatures in this range combined with 1000 to
500 mb thickness values around 492 DM will be capable of
producing surface temperatures in the 30s and 40s below for lows.
Increased day light and sun angle in February will help modify
high temperatures into the 10s and 20s below as compared to high
temperatures during last month's cold snap that produced high
temperatures in the 40s below. At this point it appears that there
will be considerable cloudiness Wednesday and Thursday which will
moderate the cold temperatures however as the upper level trough
axis passes into the eastern interior skies will likely scatter
out and provide for maximal radiational cooling and possibility
for lows in the 30s and 40s below Friday, Saturday and possibly
Sunday for the central and eastern interior.

The model suite introduces considerable spread on solutions early
next week with the ECMWF and Canadian models keeping the cold air
mass over interior Alaska into early next week and the GFS
presenting a solution that would produce rapid and substantial
warming at least in the hills as cold air will persist in valleys
longer. The model suite spread from run to run and between model
families is leading to low forecast confidence early next week.

On the surface low clouds, fog and flurries are pushing inland
over the north slope and will push south to the Brooks Range by
this evening. Low IFR conditions noted over much of the north
slope at this time and will likely continue through tuesday
morning. A 996 mb low dropping rapidly south out of the high
arctic near Banks Island will light snow and strong winds over the
eastern north slope beginning Tuesday night and continuing into
Wednesday. Will likely need winter headline for eastern north
slope Tuesday night and Wednesday as strong cold air advection
combined with 925 mb barrier jet of 40 knots and falling snow will
likely drop visibilities below one half mile.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
None.
&&

CCC FEB 17