Scientific Forecaster Discussion
fxak69 pafg 142122
Northern Alaska forecast discussion
National Weather Service Fairbanks Alaska
122 PM akdt Mon Oct 14 2019
Synopsis...high pressure over the interior will keep most of the
forecast area under clear to partly cloudy skies, and even the
Arctic coast and Brooks range will see some clearing skies as
offshore flow kicks in. The West Coast is being impacted by the
remnants of Typhoon Hagibis and the winds will increase a bit this
evening south of the Bering Strait and over the lower Yukon
Delta, then diminish Tuesday afternoon. A few showers will also
move over that area, but no significant precipitation is expected.
Models...14/12z solutions are in pretty good agreement in the
short term, but there is a wide variety of solutions in the
extended periods. Run to run has been good short term, but there
have been major changes in the solutions for the late midrange and
extended periods, so will lean more on the ensemble mean forecast
for those periods to maintain continuity. Short term probability
of precipitation solutions look reasonable, so will use an equal
blend for the short term.
Aloft...at 500 hpa...544 dam high is over the central Brooks range
this afternoon and will drift northwest over Wainwright by noon
Tuesday, then slowly north over the Arctic to 250 nm north of
Point Lay Thursday morning. The stacked remnants of Typhoon
Hagibis have moved over the central Bering Sea with a 500 dam low
250 nm southwest of St Matthew island this afternoon. The low will
move over the Gulf of Anadyr Tuesday afternoon as it weakens to
504 dam and will eventually merge with a 501 dam low over the
western Bering Sea. A 506 dam low will develop 150 nm north of
Kiska and move east over the pribilofs Wednesday morning, then
slow and merge with the low that was over the western Bering Sea
as it moves over the central Bering Sea. A 516 dam low will
develop over Sand Point Wednesday afternoon and move south of the
Gulf of Alaska Thursday. Troughing will develop over southcentral
Alaska tonight and move over the Alaska Range and southeast
interior tonight. A 526 dam low will develop over the western
Alaska Range and move over McGrath Tuesday afternoon then
dissipates as the troughing moves over the northern interior
Wednesday morning where it will persist through Thursday. At 850
hpa...a large pocket of 0c+ temperatures over the West Coast and
Northwest Arctic coast this afternoon with the -10c isotherm
hanging on over the southeast interior and eastern Brooks range.
By Tuesday afternoon there will still be a pocket of 0c+
temperatures over most of the Arctic and Chukchi Sea region, and
a pocket of the -10c is hanging on over the southeast interior. By
Wednesday afternoon The Pocket of 0c+ continues to hang over the
Arctic, but is moderating, while the pool of -10c temperatures
expands up the border and over the upper Yukon Flats and the
eastern Brooks range.
Surface...broad area of high pressure extends from Canada to the
western interior and northwest over the Arctic. Weak troughing
north of the Brooks and Alaska ranges will persist. The remnants
of Typhoon Hagibis are 150 nm southwest of St Matthew at 953 mb
and will move to the Gulf of Anadyr by Tuesday afternoon as the
high pressure over the state is pushed north and east. Low
pressure in the Gulf of Alaska will remain with several lows
moving around the Gulf in the flow. A 971 mb will develop over
Kiska and move east to the pribilofs at 968 mb then over Bristol
Bay Wednesday afternoon.
Arctic coast and Brooks range...clearing skies as high pressure
build over the area, but as it lifts north of the coast, expect
stratus to return over the coast with some flurries and patchy
fog, but that will not occur until Tuesday afternoon/evening.
Winds will be swinging around to east and increasing this evening
to 10 to 20 mph gusting to 30 mph. Winds near Kaktovik will
continue to increase Tuesday to 20 to 30 mph gusting to 40 mph.
Highs in the 20s, lows in the teens.
West Coast and western interior...remnants of Typhoon Hagibis will
spread some showers to the coast south of the Bering Strait, and
continue to bring strong winds to the lower Yukon Delta and St
Lawrence Island. Winds will diminish Tuesday afternoon/evening,
but showers will continue to move through the area through
Wednesday morning. From the Bering Strait south winds east to
southeast 30 to 40 mph gusting around 60 mph on St Lawrence
Island, with winds 20 to 30 mph gusting around 40 mph for the
remainder of the coastal areas and the lower Yukon Delta. Chukchi
Sea region will remain partly cloudy with winds from Kotzebue
north, southeast to south, at 20 to 30 mph gusting around 40 mph
this afternoon, diminishing tonight to 10 to 20 mph gusting to 30
mph. West of Kotzebue winds will be east to southeast at 10 to 20
mph diminishing to around 10 mph tonight. Temperatures will be a
bit warmer with highs in the 30s and 40s, while lows will be in
the 20s to around 30 along the coast and in the teens further
Central and eastern interior...mostly clear skies the tonight with
a few clouds moving through the area tomorrow night. Winds
generally light from the northeast, but some gusty winds on the
summits in the interior to 20 mph, and in the upper Tanana Valley
to 30 mph tonight. Highs in the 20s to around 30 for most
locations, with lows in the teens and 20s. Temperatures will be a
bit warmer in the windy locations.
Coastal hazard potential days 3 and 4...none.
Extended forecast for days 4 to 7...troughing will remain to the
west and south of the area with ridging over the Arctic.
Precipitation will generally be over the West Coast and south of
the forecast area, but may sneak in over the southeast interior
Friday night and Saturday. Expect cloudy condition in the Arctic
with flurries or periods of light snow. The West Coast will see
rain and snow showers.
High Wind Warning for akz213.
Small Craft Advisory for pkz225-pkz230-pkz240-pkz245.
Gale Warning for pkz200-pkz210-pkz215-pkz220.