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Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
222 PM akst Thu Nov 21 2019

Synopsis...
a southerly flow pattern will push a series of weather systems
from Bristol Bay north over Alaska through the weekend, bringing
snow to the West Coast and western interior with 2-6 inches of
snow from today through Sat. This pattern will also cause strong
warm southerly Chinook winds across the Alaska Range, causing the
eastern interior to have periods of light snow, and a bring a
chance of freezing rain over the southern and eastern interior.



Aloft...
a series of strong short wave troughs will rotate out of the base
of the trough and move northeast across Alaska, pulling the long
wave trough east to a position over Mainland Alaska by Sat. Each
of these short waves will bring a bought of snow to the West Coast
and western interior, with lesser amounts of snow in the eastern
interior due to the strong Chinook conditions occuring there. This
strong Chinook will allow for a chance of freezing rain in the
southern and eastern interior through Fri that will push further
east on Fri night as the Chinook weakens.

Surface...
a 970 mb low in Bristol Bay will move north as a 968 mb low by
3am Fri, to Galena as a 975 mb low by 3pm Fri, then weaken slowly
through Sat. A weak low will remain over the Yukon Delta on
Saturday. A strong low will move into the western Bering and the
associated front will hit the West Coast by Monday evening.

Interior...Chinook flow will continue over the interior through
Friday. Wind advisories are still in effect for zone 223, 225 and
226 through noon on Friday. Temperatures will remain above normal
under the Chinook flow through Saturday. The western interior and
northern interiors will see 1 to 3 inches of snow through Friday
evening, but downsloping will limit the central and eastern
interior precipitation. There remains a slight chance of freezing
rain mostly south and east of Fairbanks as Chinook flow off of
the Alaska Range keep temperatures aloft warmer...however the
warmer and dryer Chinook flow will also limit the chance for
precipitation.



West Coast...low pressure system will bring another
2-4 inches of snow to the West Coast and western interior Fri into
Sat, while just a chance of snow comes to the eastern interior
Fri into Sat. Expect north winds gusting 55 mph from Point Hope to
the Bering Strait to St Lawrence Island Fri into Fri night then
decreasing slowly Sat. This will cause lake affect type snow
squalls over zone 213 Fri into Sat and brief periods of whiteout
conditions. Since temps are dropping below 25f now, this will also
bring freezing spray to zone 213, especially Savoonga now through
Sat and could cause ice build up on power lines which could cause
power outages.

Coastal hazard potential days 3 and 4...
a strong storm is forecasted to move east across the Bering Sea
next Mon-Wed bringing the potential for heavy snow, strong winds
to the West Coast and western interior next week, and possible
high sea levels to the West Coast.

&&

Afg watches/warnings/advisories...
Wind Advisory for akz223-akz225-akz226.

High surf advisory for akz213.

Winter Weather Advisory for akz215-akz227.

Heavy freezing spray warning for pkz210-pkz220-pkz225-pkz230-
pkz235.

Small Craft Advisory for pkz230-pkz235.

Gale Warning for pkz210-pkz220-pkz225.
&&

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