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000 
FXAK69 PAFG 241251
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
451 AM AKDT Mon Apr 24 2017

.SYNOPSIS...
Aloft...
A ridge over Northern Alaska will weaken slowly through Wed then
strengthen slowly in the second half of the week. Temperatures
will remain above normal over the area south of the Brooks Range,
while the North Slope will remain below normal through at least
mid-week. Interior Alaska will see a general increase in clouds
through mid-week but remain generally dry while the West Coast has
increasing chances of precipitation through mid-week. 

A short wave trough in the Gulf of Alaska will move north over 
the Alaska Range Mon night, to Bethel to Eagle by 4pm Tue, and to 
the Bering Strait to Circle by 4pm Wed. Will see moisture increase
ahead of this trough with a chance of precipitation along with 
the trough. Will see weak downslope winds along the Alaska Range 
following the trough Tue. 

A second short wave trough in the high Arctic will move south
along the Arctic Coast of Alaska Tue night and along the Brooks
Range Wed. Expect this to continue feed of low level clouds,
flurries and fog into the North Slope with clearing behind this 
trough.

Surface...
A cold front stretching from 300 nm north of Barter Island to 
Barrow to Cape Lisburne will move to Demarcation Point to Cape 
Lisburne by 4pm Mon...then along the Brooks Range by 4am Tue and 
then persist into Wed. A large area of stratus along with fog and 
flurries is visible on Satellite extending north to 80N. Expect 
the stratus along with fog and flurries to push south over the 
North Slope with the front and persist into Wed. Will see some 
clearing Wed from the north with the trough aloft mentioned 
above.


Patchy low fog currently along the Arctic Coast will thin by 
afternoon as the stratus lay mentioned above moves over the
surface fog. 

A 1028 mb high over the Chukchi Sea north of the front will build
southeast over the Chukchi Sea today and persist into Wed. This 
will cause north winds along the capes of the West Coast and
through Brooks Range passes to persist through Wed. 

An Arctic front stretching from Savoonga to Nome to Indian
Mountain to Circle will persist through Wed. Expect any
precipitation to fall as snow north of this front and mixed along
and south of the front...with mainly liquid further south of the
front. 

A weak lee side trough over the Tanana Valley will persist 
through Tue. This will cause gap flow winds through Alaska Range 
passes through Tue...with some increase Tue as the trough aloft 
passes north and enhances the lee side trough. 

&&

.DISCUSSION...
Models initialize 10 to 20 dm too weak with heights in the high
aloft over Northern Alaska. Expect this to cause high aloft to
weaken slower than models indicate. Models agree on large scale 
pattern of ridge weakening slowly through Wed then rebuilding 
slowly through next weekend. The GFS again over does precipitation
in the eastern Interior for the first several days. With weak
downslope flow through Tue the precipitation in the eastern 
Interior will remain nil today with just isolated showers from 
Tue into Wed along the arctic frontal boundary. GFS and ECMF 
precipitation more similar over the West Coast and a mix of them 
seems reasonable.

&&

.FIRE WEATHER...
Today will be slightly higher rh than Sun...then increasing
gradually through Wed as clouds increase. Highs will be in the 50s
south of the arctic front with lows in the 20s and 30s. Alaska
Range passes will see gusts to 30 mph through Tue. Could see 
gusts spread north to Delta Junction on Tue with near red flag 
conditions, but expect rh higher than 25% on Tue in the gusty
areas. 

&&

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

Brisk Wind Advisory for PKZ220-PKZ225.

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