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000 
FXAK69 PAFG 221338
AFDAFG

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
438 AM AKST Wed Nov 22 2017

.DISCUSSION...

Models...Better agreement in the short term out to 48 hours or so
with the latest solutions. Some disagreement on what the surface
low near the Arctic Coast will be doing beyond 48 hours. Will 
be using more of an equal blend with the exception of leaning
toward the GFS for the wind fields. The 22/00Z solutions did 
initialize okay against the 22/06Z surface analysis for positions
and central pressures. Coastal Flood guidance has done well and
most areas will see falling sea levels through the day today. 

Aloft...at 500 hpa...A 504 dam low 150 nm northwest of Point 
Lay will remain stationary, then move east. The associated
shortwave extends southeast over Bettles to Paxson to Cordova this
morning and will move east to over the Yukon Territory by late
this evening with a 504 dam low developing over the Eastern Arctic
Coast and trough extending west to the stationary low. A 508 dam
low will develop over St Matthew Island this morning and move over
Nunivak Island early this evening at 504 dam, then dives southeast
over Kodiak Island by Thursday morning. A weak ridge lies from a
589 dam high in the North Pacific south of Kodiak Island over the
Kenai Peninsula then northwest to the Seward Peninsula this
morning and will pull south and move east to lie South over the
Alaska Range and east of Cook Inlet by Thursday morning. A ridge 
over the Western Bering Sea will move to the Eastern Bering Sea 
and extend northeast over the Seward Peninsula Thursday morning, 
and by Thursday afternoon will lie over most of the West Coast and
Western Interior south of the Brooks Range and east of the 
Chukchi Sea. The ridge will work east and south, but weaken 
significantly Thursday night and dissipate Friday morning. By
Friday morning troughing will be over the eastern Half of the
state with a 510 dam low over Nuiqsut, and Ridging will moving be
over the Eastern Bering Sea, Chukchi Sea, and West Coast. At 850 
hpa...Temperatures over the forecast area generally -11C to
-16C.

Surface...Strong low that was over the Western Chukchi Sea
yesterday has moved to 100 nm northwest of Point Lay at 980 mb and
will become stationary as it weakens through tonight before moving
slowly east. Weak high pressure continues over most of the Central
and Eastern Interior with a 1009 mb high in the Upper Yukon Valley
in the Yukon Territory. A 976 mb low has moved to 100 southwest of
St Matthew Island this morning and will move to Nunivak Island
this evening at 969 mb. A relatively tight pressure gradient 
around the low will move over the Lower Yukon Delta this afternoon
and east to south winds will increase from Nome south and
southwest of Ruby. Ridging over the interior will persist as the
low over the Arctic moves east over the coast through Friday, and
th low over Nunivak Island moves southeast and merges with a low
in the Western Gulf of Alaska Thursday afternoon. A strong weather
system will move to the west coast Friday night.

Arctic Coast and Brooks Range...Blizzard to near Blizzard
conditions continue over the Western Brooks Range and Northwest
Arctic Coast. Peak winds reached almost 90 mph from the storm but
are diminishing as the low weakens just offshore. Conditions will
be improving through the day. Expect periods of low clouds and
snow through the day, with accumulations up to 5 inches, but
generally 1 to 3 inches. Locally blowing snow will reduce
visibility after Blizzard conditions end. Strongest winds will be
west of Point Barrow with southwest winds gusting to 60 mph near
Point Lay this morning. Temperatures slightly cooler. 

West Coast and Western Interior...Blizzard conditions primarily
north of the Seward Peninsula this morning will diminish through
the day. However, a rapidly moving low in the Bering Sea will move
to Nunivak Island this evening spreading Blizzard conditions to
the lower Yukon Delta by this afternoon as winds ramp up with
gusts to 70 mph around Cape Romanzof and gusts to 60 mph around
Marshall. The remainder of the Delta will have winds gusting to
around 45 mph. Heavy snowfall can be expected in the lower Yukon
Delta as well with 6 to 12 inches of snow. Temperatures slightly
warmer today, then cooling. 

Central and Eastern Interior...Cloudy conditions will prevail 
today with light snow or flurries, then decreasing clouds this 
evening with falling temperatures. Snowfall today up to 2 inches. 
Winds light and variable. 

&&

Coastal Hazard Potential Days 3 and 4...Models still bringing a 
storm to the Bering Strait Saturday that has the potential to 
produce high surf along the southern Seward Peninsula, and the 
Chukchi Sea Coast north of Cape Espenberg. 

&&

Extended Forecast days 4 to 7...Better agreement in the guidance 
for the mid and extended periods with the latest solutions. Expect
high pressure building over the Arctic, and Central and Eastern
Interior with cooling temperatures. Lows on the weekend falling
into the 20s below or colder, then warming a bit to start the
week. No new snow expected in the interior through the middle of 
next week. 

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Coastal Flood Warning for AKZ207-AKZ211.

Coastal Flood Advisory for AKZ209.

Winter Storm Warning for AKZ212.

Blizzard Warning for AKZ201-AKZ205-AKZ207-AKZ213-AKZ214-AKZ215.

Heavy Freezing Spray Warning for PKZ200-PKZ220-PKZ225-PKZ230-
PKZ235.

Gale Warning for PKZ200-PKZ210-PKZ225-PKZ230-PKZ235.

Brisk Wind Advisory for PKZ240-PKZ245.

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