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FXAK69 PAFG 202305 CCA
AFDAFG

Northern Alaska Forecast Discussion...CORRECTED
National Weather Service Fairbanks AK
305 PM AKDT Sat Oct 20 2018

.DISCUSSION...
An active weather pattern for northern Alaska this week as a
series of storms moves north out of the Gulf of Alaska and into
the interior.

The long wave pattern consists of a trough over the Bering Sea
and Western Alaska and a ridge over northwestern Canada and
eastern Alaska. A series of strong shortwave troughs aloft and
strong surface low pressure systems will push north from mid-
latitudes into the northern Pacific and Gulf of Alaska and will
produce periods of rain and snow in the interior as well as
produce strong winds through the passes and along the northern
foothills of the Alaska Range through the rest of the week.

The 12z model suite initialized reasonably well against the 12z
surface analysis and verified well against the 18z surface
analysis. Model spread is minimal in the short range however the
models have consistently had difficulty on the track and strength
of the lows moving north out of the low latitudes into the
northern Pacific and Gulf of Alaska over the past several days and
see no reason for that to change looking forward to the series of
low pressure systems progged to move north out of the gulf of
Alaska into Alaska over the next several days.

System number one is currently located just east of Fort Yukon
and will continue to weaken and move northeast into the Mackenzie
Delta. This system brought the seasons first observed snowfall to
Fairbanks this morning with trace amounts to around an inch
reported at valley level and in town while 1 to 2 inches was
reported in the hills around Fairbanks. 2 to 4 inches was reported
above 2000 feet in the hills north and east of Fairbanks.

System number two, a 970 mb low currently located 300 nm south of
Kodiak Island will deepen to around 967 mb this evening and then
start to weaken to around 970 mb Sunday morning as it moves north
over Kodiak Island. Winds aloft ahead of the low will produce
gusty winds through the Alaska Range Passes where a Wind Advisory
has been issued for the Eastern Alaska Range beginning at
midnight tonight and continuing into Monday morning. A deep lee
side trough will develop along the northern foothills of the
Alaska Range and will likely produce a weak Tanana Valley Jet and
will produce gusty southeast winds in the Delta Junction area.
Moisture with th front with the second system will be limited over
much of the eastern and central interior with drying down slope
chinook winds with only a slight chance of rain or snow expected
in these areas while there will be a chance of rain and snow in
the western interior and west coast. North winds will increase
tonight and continue Sunday and Monday through the Bering Strait
as the low pressure system moves west toward Nunivak Island.

System number three moves rapidly northwest into the northern Gulf
of Alaska Tuesday as a 970 mb low. A front moving northwest
around the low will bring a mixed bag of precipitation into the
southeast interior Tuesday morning and into the central interior
Tuesday afternoon. The system make landfall int Prince William
Sound as a 975 mb low and continues to wrap precipitation into the
eastern and central interior Tuesday night and Wednesday.
Considerable spread exists on the track, position and strength of
this system with precipitation type depending on time of day that
the precip falls and elevation. The potential exists again over
the eastern and central interior for rain, freezing rain and snow
with this system.

System number four races north into the northern Gulf of Alaska
as a very strong low dropping to around 955 mb to 960 mb Thursday
morning. Expect another round of strong winds through the Alaska
Range Friday as well as another round of precipitation over
northern Alaska Friday and Saturday.

A fifth system moves north into the northern Gulf of Alaska
Saturday night and Sunday of next week.



Coastal Hazard Potential Days 3 and 4...None.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Wind Advisory for AKZ226.

Winter Weather Advisory for AKZ220.

Small Craft Advisory for PKZ200-PKZ210-PKZ220-PKZ240-PKZ245.

Heavy Freezing Spray Warning for PKZ240-PKZ245.
&&

$$

CCC OCT 18