textproduct: Fairbanks

SYNOPSIS

A departing front across the central/eastern Interior north to the Arctic Coast will continue to shift east today with scattered rain and high elevation snow showers, as breezy winds and drier conditions build in out of the west. Our next system will be tracking southeast out of the Chukchi Sea tonight into Sunday and Monday with another round of rain, snow, breezy winds, and cooler temperatures. While conditions will trend drier midweek across the Interior under the increasing influence of high pressure, a series of shortwave troughs working over Western Alaska and the North Slope will help keep rain/snow chances around throughout the week. Looking ahead, a large low pressure system will enter the Bering Sea on Wednesday, tracking northeast towards western Alaska Thursday into Friday. Details on the exact track, strength, and impacts of this system will come into focus over the coming days.

KEY MESSAGES

Central and Eastern Interior...

- Rain and high elevation snow showers will continue to track east today, as breezy winds, dry conditions, and clearer skies build in out of the west. Additional rainfall amounts through tonight will be around a T-0.25" with highest totals east of Fairbanks.

- Breezy west/southwest winds are expected across much of the Interior today, with gusts peaking around 25-35 mph for most locations.

- Following a brief period of drier weather today into tonight spreading west to east, another round of rain and high elevation snow will move across the Interior Sunday into Monday. Breezy winds will also accompany this system, with gusts peaking around 20-40 mph, strongest across higher elevations and the Tanana Valley.

- Rainfall accumulations Sunday into Monday are expected to be around 0.10-0.50", locally higher in the Alaska Range and Middle Tanana Valley around Delta Junction of 0.50-1.00". Snow levels around 3-4,000 feet will support snow across higher elevations of the Interior, with heaviest totals in the Alaska Range.

- Highs are expected to remain in the 40s and 50s through early next week, with overnight lows in the 30s to low 40s.

West Coast and Western Interior...

- Dry weather is expected today with a mix of sun and clouds for most of the day, ahead of another low moving southeast from the Chukchi Sea later today into tonight and Sunday. This system will bring another round of rain, high elevation snow, and breezy winds through Monday.

- Rainfall accumulations tonight through Monday are expected to be around 0.10-0.50", with dry conditions favored out at St. Lawrence Island. Snow levels around 1-2,000 feet will support light snow across higher elevations of the Seward Peninsula, Western Interior, and Brooks Range.

- Winds will pick up out ahead of the next low, with gusts of around 20-30 mph across the West Coast out of the southwest. Winds will increase on Sunday, shifting to the northwest with gusts up to around 25-45 mph.

- Highs are expected to be warmest today in the 50s to low 60s, dropping to the the 40s/50s early next week, with overnight lows in the 30s and 40s.

North Slope and Brooks Range...

- Rain and high elevation snow across the eastern North Slope and Brooks Range will continue to shift east today, with pockets of a wintry mix expected at times. Additional snow amounts will remain focused in the Brooks Range around a T-2".

- Winds will remain strongest today across the eastern Arctic Coast around Kaktovik, western Arctic Coast around Point Hope, and at Atigun Pass with gusts peaking around 30-40 mph.

- Following a brief period of drier weather today into tonight spreading west to east, another round of rain and high elevation snow will move across far Northern Alaska tonight into Sunday and Monday as a system tracks southeast from the Chukchi Sea.

- Rainfall accumulations tonight through Monday are expected to be around 0.10-0.50" (highest farther west), with drier conditions expected around Deadhorse to Kaktovik with a T-0.10". Snow levels around 1-2,000 feet will support light snow across higher elevations of the Brooks Range, with around a T-2" expected.

- An uptick in winds will accompany this system, with gusts peaking around 15-30 mph, strongest across the Arctic Coast and higher elevations of the Brooks Range.

- High temperatures today will be warmest farther west in the 50s to around 60, as locations farther east stay in the 30s/40s. That warmer airmass will shift east Sunday as highs stabilize starting Monday in the 30s/40s. Overnight lows will be in the 30s/40s, locally cooler in the Brooks Range in the 20s/30s.

SHORT TERM

Today through Monday Night. The main concern through the short term will be the transition from the departing Bering Sea low to the next system dropping southeast from Siberia and the Chukchi Sea. The current system will continue to pull away Saturday, allowing a brief period of more scattered precipitation coverage and partial clearing before the next low moves into northwest Alaska Sunday and then tracks southeast across the Interior Sunday night into Monday. This second system will bring another round of widespread precipitation, breezy winds, and a notably cooler airmass to Northern Alaska.

Behind the departing low, a broad trough/upper low will shift east across the state Saturday while drier air works eastward from western Alaska. This will result in precipitation becoming increasingly showery and scattered through Saturday, with the greatest coverage across the Brooks Range and northern/eastern Interior as the trough axis moves through. A period of relatively drier weather is expected Saturday night, particularly across the western and central Interior, although lingering showers will remain possible near the Brooks Range and Alaska Range. Low-level flow will turn increasingly west to northwest behind the departing low, with gusty winds developing as the pressure gradient tightens between the departing low and building high pressure to the west. Gusts of 25-35 mph are expected across portions of the Tanana Valley as winds shift northwest. Despite the temporary influx of drier air, cool temperatures and residual cloud cover are expected to remain.

Attention then turns to the 995 mb low that will drop southeast from Siberia across the Chukchi Sea late Saturday into Sunday. Increasing moisture ahead of the system, combined with large- scale ascent associated with the approaching upper-level low, will spread precipitation back into western and northern Alaska Sunday. Precipitation will initially favor the West Coast, western Interior, and Brooks Range before expanding eastward into the central and eastern Interior Sunday afternoon into the evening. Current guidance supports generally 0.10-0.50 inches of rain across much of northern Alaska Sunday into Monday, with locally higher amounts around 0.50- 1.00 inches favored along the Alaska Range where northwest flow will enhance orographic precipitation. The upper Tanana Valley, however, should remain comparatively drier given the orientation of the moisture plume.

As the low continues southeast across western and central Alaska Sunday night, the associated trough will deepen and temperatures will fall as colder air wraps southward behind the system. Rain will remain widespread through Monday, with periods of moderate precipitation possible where the surface low and midlevel trough provide stronger forcing. Across the Brooks Range, precipitation will gradually transition from rain to a rain/snow mix and then primarily snow at higher elevations Sunday night into Monday as colder air filters southward. Snow levels will lower through the period, with snow becoming increasingly likely at pass level and higher terrain. Current guidance supports generally a trace to 2 inches of snow across the Brooks Range, with the highest amounts favored near the summits. Snowfall will also increase across the higher elevations of the Alaska Range though snow accumulations are expected to remain confined to higher terrain and not significantly impact the passes. Lower elevations will remain primarily rain or a rain/snow mix with little accumulation expected. The pressure gradient surrounding the low will also produce another period of breezy conditions Sunday into Monday, with the strongest winds likely along the Western and Arctic Coasts and in favored terrain. Coastal wind gusts around 30-45 mph remain possible as the low moves southeast, while inland winds will generally be lighter.

By Monday night, the low will continue to move away while colder air settles across northern Alaska. Cloud cover and lingering precipitation will temper the magnitude of the temperature drop, but temperatures will fall into the mid to upper 30s across much of the Interior, with lower temperatures possible in favored valleys and higher elevations. Ensemble guidance indicates 850 mb temperatures falling to roughly 0 to -4C with this system. Any breaks in the cloud cover Monday night could therefore result in locally colder temperatures than currently forecast.

LONG TERM

Tuesday through next Saturday. Following a departing low now centered in the Gulf of Alaska on Tuesday, the upper level pattern will then become dominated by upper level ridging over southwest Alaska/eastern Aleutians and upper level troughing over the High Arctic between 70N and 80N. Moisture working overtop this ridge to our southwest will support a series of shortwaves lifting north towards the Y-K Delta with scattered rain showers, while the H5 low over the High Arctic will do the same with scattered rain and snow showers across the North Slope and Brooks Range. The Interior will remain in between these features, as conditions trend warmer and drier and precipitation chances become increasingly isolated.

By Wednesday, that ridge to our south will shift east, allowing for a large area of low pressure to lift northeast and enter the southern Bering Sea. The surface low is expected to strengthen late Wednesday into Thursday, as atmospheric river moisture begins to lift north through the eastern Bering Sea into southwest Alaska as winds ramp up along the West Coast. The steering flow of what guides this low is the most uncertain at this point, with the strength peaking currently at around 970 mb in the Bering Sea. This steering flow will determine what track the low center takes, with ensembles split on keeping it situated farther west through the weekend versus a more northeasterly track. Details on the exact track, strength, and impacts of this system will come into focus over the coming days, with the bigger trends centering around gusty winds across western Alaska, moderate to heavy rain, and higher water levels across the West Coast. Stay tuned.

COASTAL HAZARD POTENTIAL

Breezy southwest winds with gusts up to around 20-30 mph along the West Coast today will shift to the west/northwest Sunday into Monday and strengthen, with gusts up to around 25-40 mph supporting onshore flow. Minor coastal impacts are expected, with water levels for most communities reaching 1-2 feet above the normal high tide. The Kotzebue Sound, Bering Strait, and Interior Norton Sound are expected to see the highest water level rises closer to 2 feet. Following this system, attention then turns to a large low entering the Bering Sea on Wednesday, tracking northeast towards western Alaska Thursday into Friday. Details on the exact track, strength, and impacts of this system will come into focus over the coming days.

FIRE WEATHER

Upper level ridging will continue to shift east across the Interior today, as remaining rain showers work towards the Alcan Border with an additional T-0.25" of rain expected east of Fairbanks. Elevated 925 mb winds today will lead to breezy conditions, with gusts for most locations peaking out of the W/SW around 25 to 35 mph. MinRHs this weekend will continue to be driest in the Upper Tanana and Fortymile region around 40-50%. Our next system will work southeast from the Chukchi Sea over the Interior Sunday into Monday, with widespread rain, high elevation snow, breezy winds, and improving RH. Rain totals Sunday into Monday are expected to be around 0.10- 0.50", locally drier across the Tanana Flats where a T-0.10" is expected. Snow levels will drop to around 3-4000 feet, supporting snow across our highest elevations. Winds are expected to peak Monday into Monday night, with gusts to around 20-40 mph out of the W/NW expected, strongest in the Alaska Range and Tanana Valley. Following a cooler and wetter start to next week, conditions will trend warmer and drier towards midweek as MinRHs starting Tuesday and Wednesday drop to around 40-50% across the Upper Tanana and Fortymile region.

HYDROLOGY

Following around 1 to 2 inches of rain across much of the West Coast and Western Interior over the past two days, local areas rivers and streams have trended higher but no flooding is expected. Additional rainfall is expected (generally in the 0.10-0.50" range) late Saturday through Monday as the next system moves through the area from the northwest.

AFG WATCHES/WARNINGS/ADVISORIES

AK...Winter Weather Advisory until 4 PM AKDT this afternoon for AKZ809. MARINE...Small Craft Advisory from 10 PM this evening to 4 AM AKDT Sunday for PKZ801-803. Small Craft Advisory from 1 AM to 6 AM AKDT Sunday for PKZ804>807-817-852-854. Small Craft Advisory from 4 PM this afternoon to 7 PM AKDT this evening for PKZ807. Small Craft Advisory from 10 PM this evening to 1 AM AKDT Sunday for PKZ850. Small Craft Advisory from 10 AM this morning to 10 PM AKDT this evening for PKZ851.