Flood in Alaska, May 9 to 13, 2022

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
213 PM AKDT Mon May 9 2022

.SYNOPSIS...Low pressure system is moving east and the weather
front will move east of the AlCan tonight or early Tuesday. Expect
some patchy dense fog in the Interior valleys Tuesday morning,
then some clearing. Cooler temperatures continue.

&&

.DISCUSSION...

Models...09/12Z solutions have changed up a little and the next
system will not be as strong and they all agree on that. For the
Extended periods not many differences as the long wave trough digs
south over the state. Some differences in the extended periods as
some solutions want to dig another strong shortwave into the
longwave trough, so for now will lean away from them and lean more
on the Ensemble mean. A mix of precipitation this evening with it
tapering off overnight. The next system being weaker, we will drop
the probabilities some as it moves into the Central Interior and
stalls before falling apart. Temperatures in the database for the
Upper Yukon Flats a bit high again today so will bring them down a
couple degrees, otherwise the current database looks good. For
the winds will include the current database with a lean toward
the stronger Canadian solution for the short term.

Aloft...At 500 hpa...A 521 dam low is 400 nm northwest of
Utqiagvik with trough extending southeast to a 524 dam over
Deadhorse and a 526 dam low over Stevens Village this afternoon,
then south to a 531 dam low over Whittier. Ridging is pushing
north over the Bering Sea and Chukotka west of the Dateline as a
576 dam high has moved to 150 nm north of Amchitka. Tuesday
morning the trough will slide east as it extends from the
northwest Arctic southwest to a 529 dam low 100 nm north of
Kaktovik, then south to a 529 dam low over Salcha, to a 525 dam
low 100 nm southwest of Yakutat. Ridging will rotate east to lie
over 170W as the high moves to 100 nm north of Adak. Tuesday
afternoon the troughing will be over the AlCan Border and Beaufort
Sea with a 527 dam low 100 nm southwest of Yakutat. Ridging will
continue to rotate east and will lie from north of Utqiagvik over
Utqiagvik then southwest over Unalakleet to 575 dam high 150 nm
north of Adak. A 517 dam low will move to 200 nm northwest of
Wrangel Island with a trough extending southeast over the central
Chukchi Sea and Bering Strait. At 850 hpa...-10C isotherm has been
pulled south over the West Coast to Norton Sound and the Lower
Yukon Delta. This pool of cold air will move over the Middle
Yukon Valley by Tuesday morning, then moderates. The remainder of
the area will have temperatures range from around 0C to -10C.

Surface...Low pressure has moved across the state with a 1003 mb
low near Kaktovik, a 1005 mb low near Cordova, and a 999 mb low
near Whitehorse YT. High pressure is pushing north across the
Chukotsk Peninsula and Chukchi Sea from a 1034 mb high 150 nm
northwest of Nikolski. A 997 mb low is spinning up on the Siberian
Coast 400 nm west of Wrangel Island. As the weather front exits
the state to the east tonight the low near Kaktovik will move into
the northeast Arctic at 1008 mb, while the low near Cordova will
move to 100 nm southwest of Yakutat at 999 mb, and the low will
persist near Whitehorse YT at 1003 mb. High pressure will move
over the West Coast pushing north over the Northwest Arctic Coast,
and east across the Arctic Plain as the high moves to 100 nm north
of Atka at 1033 mb. Low on the Siberian Coast will shift just
offshore 350 nm west of Wrangel Island as the associated weather
front moves to the Western Chukchi Sea and Bering Strait Tuesday
morning. By Tuesday afternoon the high pressure will extend from
the 1034 mb high 100 nm north of Dutch Harbor northeast across
Kuskokwim Bay to a 1020 mb high near Umiat then east across
MacKenzie Bay. High pressure will also extend northwest across the
Arctic. The low west of Wrangel Island will be 300 nm west of the
island with the front extending north of the Island, then south
along 170W. The low near Yakutat will be stationary at 1003 mb,
while the 1003 mb low near Whitehorse will drift a little to the
east.

Arctic Coast and Brooks Range...A mix of rain and snow showers
with local accumulations to 2 inches. Some clearing and lifting of
the clouds Tuesday. As the low continues to move east across
the state and high pressure build northeast into the Arctic winds
will swing around from west to northwest at 10 to 25 mph to
south and southwest. Low tonight in the teens and 20s above.
Highs Tuesday will be in the 20s to around 30.

West Coast and Western Interior...A few lingering showers,
otherwise some clearing as high pressure builds north over the
coast, then into the Western and Central Interior. Areas of fog
overnight with poor visibility Tuesday morning. Winds from the
west and northwest 5 to 20 mph. Lows tonight in the teens to upper
20s. Highs Tuesday will range from the 30s to the mid 40s.

Central and Eastern Interior...Scattered showers tapering off
overnight. Areas of fog overnight with poor visibility Tuesday
morning. Winds southwest to west 5 to 15 mph gusting to 25 mph
diminishing to less than 10 mph. Lows tonight will range from the
20s to around 30. Highs Tuesday will range from the mid 30s to
mid 40s.

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

Extended forecast for days 4 to 7...A weather system will be
exiting to the east while another moves to the West Coast. High
pressure will build north over the West Coast Saturday then into
the Central and Eastern Interior Sunday. A fast moving low will
clip the Central and Eastern Arctic Coast Saturday and Sunday
bring some cooler air and accumulating snow to the area.
Temperatures will warm a a few degrees south of the Brooks Range,
while in the Arctic they will cool a couple degrees.

&&

.Fire Weather...Chances of rain and snow through at least
midweek with no significant drying, so no concerns at this time.

&&

.Hydrology...Conditions have improved at Manley Hot Springs as the
Ice Jam released early Sunday and flood waters continue to receed.
Breakup front on the Yukon is making its way toward Fort Yukon.
Most rivers will continue to run high at around bankfull as
higher elevation meltwater and rainwater make their way into the
waterways. The water table is rising as the rivers run high, so
use caution as local erosion may occur. High temperatures will be
cooler through the week slowing down the melting process at higher
elevations. Conditions can change rapidly during breakup, so be
alert to changing conditions. For the latest river information go
to www.weather.gov/aprfc.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...

Flood Warning for AKZ221.

Flood Watch for AKZ220.

Small Craft Advisory for PKZ200-PKZ201.

Brisk Wind Advisory for PKZ215-PKZ220.

&&

SDB MAY 22