textproduct: Fairbanks

SYNOPSIS

Very cold and dry conditions will continue across much of Northern Alaska early this week, with breezy winds along the West Coast and across higher elevations. Snow chances will persist for the Upper Tanana Valley through Monday, with an additional 2-5" of snow expected. Coldest locations early this week will continue to be across the North Slope, Brooks Range, and Interior, with coldest areas dropping to the 20s/30s/40s below zero with even colder wind chills. A system moving into the Bering Sea Monday night into Tuesday will support the return of gusty winds, snow, and warming temperatures moving into the region through midweek, with an unsettled pattern expected to continue through next weekend.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Very cold and mostly dry conditions will continue across the Interior, as snow chances remain confined to the Upper Tanana Valley and Eastern Alaska Range. A Winter Weather Advisory remains in effect in this corridor through Monday for an additional 2-5" of snow.

- Coldest valleys through midweek will continue to reach down to the 20s/30s below zero with 40s below zero expected for the Yukon Flats up to Arctic Village. Wind chills will be even colder at times.

- Snow chances increase across the Interior and Alaska Range Tuesday into Wednesday, leading to warming temperatures and an increased winds. Strongest winds will be through Alaska Range Passes, around Delta Junction, and across higher elevations.

- Snowfall amounts midweek are expected to be around 1-3" with up to 3-6" for southern portions of the Alaska Range Passes.

West Coast and Western Interior...

- Very cold and dry conditions will continue across Western Alaska through Monday, with coldest locations reaching down to the 20s/30s below zero with even colder wind chills. Winds remain breezy along the West Coast and across higher elevations.

- A system moving into the Bering Sea Monday night into Tuesday will support an increase in winds, snow chances, and warming temperatures through midweek.

- Winter Storm Watches are now in effect Tuesday through Wednesday night for the Yukon Delta north to the Southern Seward Peninsula and at St. Lawrence Island where the heaviest snow and strongest winds are expected. Gusts will generally peak around 40-50 mph with a broad 2-6" of snow expected.

North Slope and Brooks Range...

- Very cold and dry conditions will continue through midweek, as temperatures reach down to the 30s/40s below zero to around 50 below zero from Toolik Lake to Umiat. Wind chills will be even colder, down to around 50-70 below zero. Extreme Cold Warnings remain in place through at least Wednesday.

- Winds will continue to remain light overall as more moderate winds remain confined to the Western Arctic Coast from Point Lay to Point Hope. Winds will see an increase regionwide Tuesday into Wednesday, with areas of blowing snow and localized blizzard conditions possible.

- Light snow chances will move into the Brooks Range and North Slope Wednesday into Thursday.

FORECAST ANALYSIS AND DISCUSSION

Today through Tuesday Night. An extensive, cold trough aloft extends from over the Canadian Archipelago southwest across the northeastern half or so of mainland Alaska, and with it, most of Alaska north of the Alaska Range is under clear skies with subzero temperatures. Especially cold temperatures in the 30s and 40s on the North Slope combined with windy conditions will yield the potential for wind chills as low as 70F. South of the AK Range, gradual cooling is expected over the next two days as the trough remains in the same general location, with lows in the Interior dropping into the negative 20s to near 40F. The southeastern Interior, including the Upper Tanana Valley (including along the AK Highway) and parts of the Fortymile Country are currently experiencing cloudier and somewhat warmer conditions than the rest of the Eastern Interior, with snow ongoing from Tok southeast and the potential for an additional 2-5 inches of total snow accumulation through Monday night before it diminishes.

Otherwise, little other impactful weather is expected until Tuesday morning, when a strong low will cross the Aleutians into the southern Bering Sea. An occluded front will push inland ahead of the low, bringing a broad area of easterly gale-force winds to the northern Bering and adjacent coastal areas. It will bring snowfall to southwestern Alaska Tuesday afternoon and evening before spreading into much of the remainder of the state from Wednesday onward. Winds will also increase across inland areas, especially at elevation, which could combine with pre-existing cold temperatures to yield cold wind chills. Blowing snow in spots is also a possibility, including across the Western Arctic Coast where blizzard conditions recently occurred. Temperatures will begin to moderate in the Interior as the coldest air mass (and corresponding trough aloft) gets shunted back into the North Slope.

Extreme Cold Watches have been upgraded to Extreme Cold Warnings for the North Slope and Brooks Range, with a Cold Weather Advisory still in effect for the Yukon Flats for wind chills down to around 60 to 70 below zero. Winter Storm Watches have also been issued for the Yukon Delta north to the Seward Peninsula and at St. Lawrence Island for light to moderate snow and gusty winds could lead to visibility below 1/4 to 1/2 mile at times. Stay tuned for updated on these over the coming days.

EXTENDED FORECAST DAYS 4-7

Wednesday through next Sunday. As snow pushes into the Central/Eastern Interior on Wednesday, snowfall rates for the system will generally fall off (even in Western Alaska) and become lighter, but there will still be the potential for up to a few inches of snow in these areas with efficient snowfall possible at times. As the trough over Northern Alaska gets pushed off to the north, southerly winds will begin to take hold across the Alaska Range, which could result in a downsloping effect reducing the amount of snow that falls on the immediate lee (north) side of the Alaska Range, although the extent to which this could occur is uncertain. There is also high uncertainty on where exactly the low moves inland, with models widely varying on the track. Regardless, a southerly track is favored relative to our area, which supports offshore winds during the initial phase of the storm's approach becoming northerly around the Thursday time frame and then briefly turning onshore/westerly on Friday before winds weaken.

Snow diminishes in the easternmost portions of the Interior by late Thursday morning, but continues across Western Alaska and overspreads the western North Slope. Thereafter, model prognosis supports much or most of the snow lifting to the north as cyclogenesis occurs Thursday/Friday over northwestern Alaska, with a weak low forming and cold air over the Bering / Chukchi Seas pushing east. By mid-to-late Friday, this could yield additional snow/snow showers in the Central/Eastern Interior and the southern North Slope. Friday into Saturday, deterministic / ensemble model guidance supports a low moving into the western Bering Sea pushing a front ahead of it into the eastern Bering Sea, bringing the potential for wind and even more snow to most of Northern Alaska, continuing the unsettled weather pattern.

Coastal Hazard Potential Days 3 and 4... As a low moves into the eastern Bering Sea on Tuesday, it will bring with it a fairly wide area of gale-force winds. Given the likely storm track to the south of Nunivak Island, these winds should remain largely easterly to southeasterly and offshore. By Wednesday afternoon and evening, winds are likely to turn more to the north, which could bring winds alongshore in parts of the YK Delta and onshore over northern St. Lawrence Island. These areas are generally heavily ice-covered, which should limit the overall flooding potential, but some water rises through cracks in the ice at Hooper Bay are a possibility.

AFG WATCHES/WARNINGS/ADVISORIES

AK...Extreme Cold Warning for AKZ801>810. Extreme Cold Warning for AKZ811. Winter Storm Watch for AKZ820>823. Winter Storm Watch for AKZ824>827. Cold Weather Advisory for AKZ833. Winter Weather Advisory for AKZ836. PK...Brisk Wind Advisory for PKZ801-803-850-852-853. Brisk Wind Advisory for PKZ802. Brisk Wind Advisory for PKZ804. Brisk Wind Advisory for PKZ805. Brisk Wind Advisory for PKZ807. Brisk Wind Advisory for PKZ811-812-816-817-857-858. Gale Warning for PKZ851. Gale Warning for PKZ854. Brisk Wind Advisory for PKZ856.