textproduct: Fairbanks

SYNOPSIS

The band of snow stretching across the Western Interior and West Coast from the Yukon Delta to the Upper Kobuk Valley weakens today before moving east across the Interior. As it weakens the strong northerly winds through the Bering Strait and across St. Lawrence Island weaken as well. The band will bring light snow to the Central and Eastern Interior as it moves east Thursday through Saturday. Cold air follows behind this band of snow bringing the lowest temperatures of the week to the West Coast and Western Interior by Friday and to the Eastern Interior by Saturday night. Higher pressure builds across the state with this cold air leading to generally clear and calm conditions for early next week.

DISCUSSION

Key Weather Messages...

Central and Eastern Interior... -A band of snow currently stretching from the Yukon Delta through the Brooks Range to the Eastern North Slope moves east Thursday bringing light snow across the Central and Eastern Interior. Amounts around 1 inch expected in areas that see snow, with up to 2 inches possible in the eastern Brooks Range. The upper Tanana Valley and Alaska highway are less likely to see any snow with any accumulations expected to be under an inch.

-Cold air sweeps across the Interior following the snow bringing low temperatures down into the -10 to -20 range by Sunday. Temperatures will be colder north of the White Mountains reaching the -20 to -30 range in the Yukon Flats.

-High pressure builds with the cold air generating generally clear and calm conditions in Interior Valleys for early next week.

West Coast and Western Interior... -Strong northerly winds through the Bering Strait to St. Lawrence Island continue to weaken. Gusts up to 60 mph possible through this evening with sustained winds weakening rapidly overnight to 25 to 30 mph Thursday and to less than 20 mph Thursday night.

-Snow continues today from Hooper Bay through the Brooks Range north of Allakaket with additional accumulations generally between 1 and 2 inches except in the lower Yukon and Yukon Delta where 3 to 4 inches additional accumulation is possible. The snow moves east Thursday and will exit the region overnight Thursday.

-Cold temperatures and building pressure follow the snow Thursday night and Friday dropping lows to the -20 to -30 range in the Western Interior and into the -10 to -20 range for the coast. Some cold spots may reach into the mid -30s.

-Generally clear skies with calm winds in the interiors over the weekend. Easterly winds strengthen along the coast Sunday night.

North Slope and Brooks Range... -Light snow continues along the Central Brooks Range and eastern North Slope today. Additional accumulations of 1 to 2 inches possible along the eastern North Slope with 2 to 3 possible in the central Brooks Range. Snow will continue through Thursday night.

-As the cold air pushes the snow east, northerly winds will increase through Brooks Range passes to 15 to 25 mph on Friday. Combined with the snow from this week travel through the passes could be impacted by blowing and drifting snow. Winds will subside Friday night and Saturday as the front bringing the cold air moves east of the passes.

-A cold air mass moves into the western North Slope Friday afternoon and reaches the eastern North Slope Saturday afternoon. This will drop low temperatures to near -20 along the coast and into the -30 to -40 range along the southern North Slope.

Extended Forecast for Days 4 Through 7... High Pressure builds across the state over the weekend and then sits there keeping conditions cold, calm, and clear. Easterly winds increase along the west coast Sunday night into Monday as a low tries to push into the Western Bering Sea.

Analysis and Forecast Confidence... A 965mb low in Bristol Bay and a 960mb low in the Aleutians weaken today and move towards the Gulf of Alaska tonight. A relatively high pressure of 997mb is located in the Arctic north of Point Barrow which has been helping to shape the deformation band bringing snow to the Yukon Delta through the eastern North Slope today. A 1028 mb high pressure system building in eastern Siberia pushes east into the Chukchi Sea Friday which, combined with the movement of the Bristol Bay low, will move the band of snow east across the state Friday through Saturday. As this band moves east it will weaken substantially causing snowfall across the eastern Interior to be less consistent than what has been seen in the Western Interior during this event. Some uncertainty lies in exactly where snow will fall, but amounts should be generally light. The remnants of the band should exit Alaska as the high out of Siberia reaches the high Arctic and begins to strengthen Saturday night to a 1038mb high by Monday morning.

This high pressure will bring colder, more dense, air to the area with the coldest being along the southern North Slope. This will help build pressure across the Interior from the 980mbs to the 1020mbs by Sunday night helping to keep conditions clear and calm in the Interior.

A 960mb low tries to move into the western Bering Sea Saturday morning, which combined with the building pressure in the Interior will create widespread easterly winds along the west coast early next week.

With the Bristol Bay low weakening conditions have improved enough that we were able to cancel the Winter Storm Warnings for the Western Interior and the High Wind Warnings for the Bering Strait. There is still a Winter Weather Advisory in effect for the Yukon Delta through Thursday morning for snow and blowing snow. Today's forecast focus has been on capturing the improving conditions along the snowband and Bering Strait as it weakens and eventually exits the region.

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

AFG WATCHES/WARNINGS/ADVISORIES

AK...Winter Weather Advisory for AKZ825. PK...Gale Warning for PKZ801-806-807-856. Gale Warning for PKZ802-854. Brisk Wind Advisory for PKZ803. Gale Warning for PKZ804. Gale Warning for PKZ805-852. Brisk Wind Advisory for PKZ808. Brisk Wind Advisory for PKZ809-855. Brisk Wind Advisory for PKZ810-811. Gale Warning for PKZ816-817-851-853. Heavy Freezing Spray Warning for PKZ816-851. Gale Warning for PKZ850. Brisk Wind Advisory for PKZ857.