Brisk Wind Advisory 153, NWS Fairbanks, AK

Northern Alaska Forecast Discussion
National Weather Service Fairbanks AK
253 PM AKDT Tue Jul 3 2018

.SYNOPSIS...
Aloft...
A long wave ridge over mainland Alaska will weaken through Thu as
a strong short wave trough over the Western Chukchi sea moves
southeast across northern AK. The ridge will rebuild Fri and Sat
before moving east on Sun and Mon as a long wave trough develops
over western Alaska. This long wave trough is expected to remain
over western AK next week. This pattern will cause warm and
generally dry conditions across the area south of the Brooks
Range through Wed, then cooler temperatures Thu. Will see
isolated to scattered showers over the southern Interior Wed PM
through Thu PM. The North Slope will have wet and windy conditions
through Thu. All areas will see warming Fri and Sat, then a
cooling trend next week.

A short wave trough from Barrow to Anaktuvuk Pass will move east
of the Alcan Border about 10 pm tonight. The mechanical lift
provided east of this trough, combined with moderate instability
over the North Slope ahead of this feature is causing isolated
thunderstorms across the North Slope today. Thunderstorms will end
west of the trough.

A second trailing short wave north of Russia will move to Barrow
to Uelen just south of Wrangel Island by 4am Wed, to Deadhorse to
the Bering Strait by 4pm Wed, to Arctic Village to Norton Sound by
4am Thu, to Inuvik to Denali by 4pm Wed, then east of the Alcan
Border Thu night. This feature will push a surface cold front
southward over Northern AK.

Surface...
A 1034 mb high over the southern Interior and Northern Bering will
weaken slowly through Thu. This is causing west winds 15g25kt over
the Eastern Interior as winds blow into the thermal trough that is
near the Alcan Border and over the NE interior. These winds will
continue into Wed and cause Red Flag conditions in the NE
Interior. Rh will remain near or above 30% in most areas,
however.

A 1010 mb low 300 nm north of Barrow will move to Banks Island as
a 1015 mb low by 4am Wed. A warm front from this low to Inuvik
will move east. A cold front extending from this low to Barrow
to the western Chukchi Sea to a frontal wave just west of Wrangel
Island. Expect rain and west winds 15-25 kt with this front.
Expect Isolated thunderstorms east of the front this afternoon and
Evening over the North Slope.

By 4am Wed the frontal wave will move 200 nm north of Nuiqsut as
a 1007 mb low by 4am Wed, with a cold front from the low to Point
Lay. By 4pm Wed the low will be 300 NM north of Barter Island as a
1001 mb low, with a cold front from the low to Arctic Village to
the Bering Strait. By 4am Thu it will be a 1003 mb low 300 NM
northeast of Barter Islands with a cold front to Inuvik to Arctic
Village to Norton Sound. By 4pm Thu the low will be near Banks
Island as a 100 mb low with A cold front to Arctic Village to
Eagle to Denali to the YK Delta. Expect rain, fog, and west winds
25-35 kt with the cold front over the Arctic Coast with gusts to
45kt over zone 204. Could see .30 inch of rain over zone 206
tonight through Wed Night.

South of the Brooks Range expect just isolated showers with the
front, with scattered showers along West Coast Capes. West winds
15-20 kt ahead of the front will turn NW 10-15kt along and north
of the front. Temperatures will could 5-10 degrees north of the
front.

An occluded front in the southern Bering will move to St Matthew
Island to the Bristol Bay coast by 4am Wed, over the YK Delta to
Iliamna by 4pm Wed, then stretch to the YK Delta east over the AK
Range Wed night. This will add isolated to scattered showers to
the SW Interior Wed into Thu, and Isolated thunderstorms to the
Alaska Range and extreme southern Interior Wed and Thu as it feeds
moisture into that area.

High pressure building over the Interior Fri will cause warming
and drying most areas.

&&

.DISCUSSION...
Models Initialize well and show similar solutions through Fri
over Northern Alaska, but large differences occur on the strength
of the low over the Bering Sea by Fri. Since there is remains of a
tropical system moving into this feature there is significant
uncertainty with that feature, but using the deeper ECMF solution
makes sense since the former tropical system should have a large
amount of moisture and energy. GFS and ECMF both develop long wave
over West Coast of Alaska next week but show significant
differences in detail so large uncertainty through next week.

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

&&

.FIRE WEATHER...
West winds 15g25kt over the Eastern Interior as winds blow into
the thermal trough that is near the Alcan Border and over the NE
interior. These winds will continue into Wed and cause near Red
Flag conditions the eastern Interior but Rh will remain near or
above 30% in most areas. In Zone 220 on Wed, RH will drop to just
under 30% Wed, but strong winds and warm temperatures combined
with dry fuels in Zone 220 have led us to issue a Red Flag Warning
there for Wed after coordination with Alaska Fire Service.
Temperatures will cool 5-10 degrees most areas on Thu, but will
see warm and dry conditions again across the Interior Fri and
Sat.

&&

.HYDROLOGY...
Water remains over Tetlin Road near Mile 6, and is expect to
remain there for the next week. River across the southeast
Interior will remain high through the week.

&&

.AFG WATCHES/WARNINGS/ADVISORIES...
Red Flag Warning for AKZ220.

High Wind Warning for AKZ204.

Small Craft Advisory for PKZ210-PKZ220-PKZ235-PKZ240-PKZ245.

Gale Warning for PKZ225-PKZ230.
&&

JB JUL 18