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000 
FXAK69 PAFG 222352
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
352 PM AKDT Mon May 22 2017

.SYNOPSIS...
Aloft...
A long wave trough over the Bering Sea will move to the 
eastern Bering and West Coast of Alaska Wed and then progress 
east to cover the Interior of Alaska on Thu. With a strong ridge 
building over NW Canada Wed we will see the flow aloft turn 
southwest on Tue and south on Wed then decreasing on Thu. This 
will feed a series of short wave troughs and their attendant 
surface systems northward over Northern Alaska through the week 
with a wet weak in store for the West Coast and Western Interior. 
This will also cause a moderate to strong chinook wind event on 
the north side of the Alaska Range Wed and Wed Night. 

Weak instability near Eagle and near Galena will allow a few
afternoon/evening thunderstorms in those areas today. After that
no thunderstorms through the weekend.

Surface...
A 1011 mb low 300 nm northwest of Barrow will move northeast
tonight and Tue. This will cause stratus and flurries/fog to
persist along most of the Arctic Coast through Tue. 

A 1000 mb low near Bettles will move to Coldfoot as a 1004 mb low
by 4am Tue...then to near Arctic Village as a 1008 mb low by 4pm
Tue. A Warm front extending east from this low will move to
Coldfoot to Inuvik by 4am Tue then dissipate. A cold front
stretching from the low to Chicken will move to ColdFoot to Eagle
by 4am Tue then dissipate over the NE Interior Tue Pm.
There are widespread showers now between the warm front and cold
front and wrapping around around south of the low. Expect .10 to
.50 inch of rain in this area tonight with the heaviest amounts
near the low center. Showers will become scattered tonight over
the Tanana Valley southwest of the cold front. 

An occluded front stretching from Gambell to King Salmon will move
to Kotzebue to McGrath by 4am Tue...to Point Hope to Denali by 
4pm Tue...to Wainwright to Old Crow by 4am Wed and then moving 
north of the Arctic Coast Wed pm. There are rain showers along 
this front now that will change to to scattered showers late 
tonight and spread northeast with the front Tue and Wed. There are
snow showers mixed on with the rain along the West Coast. 

A strong low in the southwest Bering Sea will move to the central
Bering Sea as a 993 mb low by 4pm Tue...then to near St Matthew
Island as a 1000 mb low by 4pm Wed...and then moving east and
dissipating Thu. An occluded front stretching from the low to St
Paul Island will move to the Northern Bering Sea by 4am Tue...to
the Bering Strait to Koyuk to Anvik by 4pm Tue...to Point Hope to
Kaltag to a 1002 mb front Wave low near anvik by 4am Wed...and to 
Cape Lisburne to a 996 mb wave low near Kotzebue with a cold front
from Kotzebue to McGrath by 4pm Wed. The wave low will move to
near Point Hope as 992 mb low by 4am Thu with a cold front from
POint Hope to Delta Junction. At 4 pm Thu the low will drift west
with the cold front front from Barrow to Barter Island to
Northway. 

Expect rain and snow along the occluded front with all snow above
2000 feet on Tue and Tue night. Will see significant precipitation 
along the frontal wave over the western Interior Tue Night through
Wed Night. Rain will be mixed with snow along the West Coast and
along the cold front...with all snow above 1000-2000 feet. Could 
see 2 inches of snow along the West Coast Wed and Wed night...
3-5 inches of snow Wed and Wed night above 2000 feet in the 
Western Brooks Range and other areas of the Western and Central
Interior.

&&

.DISCUSSION...
Deterministic models initialize well and show similar solutions
through Thu. Exception is the precipitation field where the NAM 
significantly under forecasts the area of precipitation. Will use 
the GFS for most fields through Thu. 

The long wave trough moves over mainland Alaska by Fri with slow 
retrogression next weekend as the long wave ridge builds over NW 
Canada and Interior AK Sun-Mon. The ECMF retrogression is slower 
than what we see on the new GFS. The ECMF has been more consistent
moving the long wave trough east in the shorter term, and the GFS
and NAM just caught up with it today, so we prefer the slower 
retrogression shown by the ECMF on the weekend.

&&

.FIRE WEATHER...
Moderate to strong chinook wind event on the north side of the 
Alaska Range Wed and Wed Night. 

&&

.HYDROLOGY...
Break up done most areas south of Brooks Range. Break up appears
to be proceeding normally north of Brooks.

Rivers generally low in the Interior. Expect .10 to .50 inch of 
rain in NE Interior tonight with the heaviest amounts near the 
low center.

Will see significant precipitation along the frontal wave over 
the western Interior Tue Night through Wed Night but since rain 
will be mixed with snow along the West Coast and along the cold 
front do not expect flooding issues.

&&


.AFG WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory for PKZ210.

&&

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