textproduct: Fairbanks

SYNOPSIS

Generally quiet and dry weather will continue across much of Northern Alaska through the weekend, as light snow chances and areas of gusty winds remain focused along the West Coast, North Slope, and Brooks Range heading into early next week. Winds will first ramp up along the Western Arctic Coast tonight into Sunday, before expanding to include the West Coast, Interior higher elevations, and the remainder of the Arctic Coast through midweek. Areas of blowing snow will be the primary hazard when it comes to stronger winds, leading to significant reductions in visibility at times especially along the Arctic Coast. Blizzard Warnings and Winter Weather Advisories are now in effect for the Arctic Coast Sunday through Wednesday, with the potential expansion of Blizzard Warning further east as winds ramp up midweek. Light snow chances will expand to the Northern Interior Sunday into Monday, along with the remainder of the Interior Tuesday into Wednesday as temperatures begin to trend warmer midweek.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Quiet and dry conditions with a mix of sun and clouds will continue through the weekend as strong inversions persist.

- Wind gusts of around 20-40 mph will continue around Delta Junction through tonight with periods of southerly gap winds through Alaska Range Passes. This will lead to locally warmer temperatures.

- Temperatures for coldest valleys through early next week will reach down to -10F to -25F with warmest higher elevations reaching into the 20s/30s.

- Outside of isolated light snow showers early next week across the Northern Interior, steadier snow chances will build in out of the southeast late Tuesday into Wednesday with best chances across higher elevations.

- Temperatures will rise mid to late week as winds ramp up across higher elevations and around the Middle Tanana Valley.

West Coast and Western Interior...

- Snow showers will continue across the West Coast and Northwest Interior through Monday night. Additional snow accumulations of a T-2" expected.

- Wind gusts up to 40 mph continue from the Bering Straight south to the Y-K Delta and in the Interior Norton Sound through tonight.

- Winds will steadily increase from the NW Arctic Coast southwest to St. Lawrence Island Sunday into Monday. Wind gusts up to 45 mph in this corridor may lead to areas of blowing snow at times.

- Temperatures hold steady into early next week with highs in the single digits and teens and lows in the single digits above and below zero with coldest locations dropping to around -15F.

- Light snow chances will increase across Western Alaska Wednesday into Thursday with light accumulations expected.

North Slope and Brooks Range...

- Light snow showers will continue through Monday, favoring the Brooks Range and Eastern North Slope. Additional snow accumulations of a T-3" expected.

- Another extended period blowing snow and low visibility is expected early to mid next week across the Arctic Coast, with a mix of Blizzard Warnings and Winter Weather Advisories now in effect Sunday through Wednesday.

- Temperatures cool down to the -10F to -30F range heading into early next week with even colder wind chills. This will be followed by a gradual warming trend through the remainder of the week.

FORECAST ANALYSIS AND DISCUSSION

Today through Monday Night. Early afternoon satellite imagery shows a mix of sun and clouds over Northern Alaska, with a 1040 mb high in the High Arctic and a series of ~980 mb lows in the Northern Pacific. A series of shortwave troughs working around the southern periphery of the ridge of high pressure to the north will continue to support scattered light snow showers through Monday, with any accumulations remaining fairly light overall. As this ridge of high pressure begins to shift south early next week, we will see a tightening pressure gradient develop overhead which will lead to increasing winds along the coasts and across higher elevations. This gradient will continue to strengthen through midweek as a now ~950 mb low builds into the Gulf of Alaska, leading to continued gusty winds into the extended forecast period.

Winds will ramp up overnight tonight and throughout the day Sunday further north and west, with strongest winds favored along the West Coast from the NW Arctic Coast to St. Lawrence Island and along the entire Arctic Coast. Blizzard Warnings and Winter Weather Advisories have been issued for the Arctic Coast Sunday through Wednesday to capture where blowing snow will lead to 1/4 to 1/2 mile visibility or less at times. Additional winter weather products will continue to be evaluated for portions of the West Coast and possibly higher elevations of the Interior dependent on where the strongest pressure gradient sets up. As high pressure shifts south over the North Slope, temperatures will continue to drop to that -10F to -30F range by Monday.

Across the Interior, conditions will remain quiet and dry overall as winds increase across higher elevations early to midweek. Very isolated snow showers will be possible primarily across the Northern and Eastern Interior but any accumulations should remain minimal. Strong inversions will continue to support temperatures in the valleys dropping to around -10F to -30F.

EXTENDED FORECAST DAYS 4-7

Tuesday through next Saturday. An active weather pattern is expected to continue into the extended forecast period, as a strong area of high pressure over the High Arctic and a series of stronger lows in the Gulf of Alaska work to support to an increased pressure gradient and moisture transport into Northern Alaska. Gusty winds will continue along the West and Arctic Coasts and across higher elevations, with areas of blowing snow where strongest winds and a blowable snowpack and or falling snow interact.

The main differences in ensemble and deterministic model guidance mid to late next week is how far north the lows in the Gulf of Alaska track. A further northerly track would lead to better moisture transport and warmer temperatures lifting over the Alaska Range into our region, while a further southerly track would lead to lesser moisture transport and not as warm temperatures building in. Our latest forecast represents a blend of these solutions, supporting increasing snow chances across much of our CWA Tuesday into Wednesday and Thursday as temperatures see a gradual warming trend. While winds broadly will begin to subside midweek, winds are looking to remain elevated along the Arctic Coast through all of next week, which may prompt expansions of current winter weather products to continue past Wednesday where they are currently in effect.

Looking ahead, the broad upper level pattern looks to remain in place mid to late week with ensembles in fairly good agreement on a broad 500 mb right of high pressure extending from the Western CONUS northwest across Western Canada into Alaska. This setup will continue to suppress any larger systems from lifting too far north into our region overall until any big changes are made aloft.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Blizzard Warning for AKZ801. Winter Weather Advisory for AKZ802>805. PK...Brisk Wind Advisory for PKZ806-807-861. Brisk Wind Advisory for PKZ810-859. Gale Warning for PKZ811-857. Brisk Wind Advisory for PKZ812-858. Brisk Wind Advisory for PKZ813-854-860. Brisk Wind Advisory for PKZ814. Gale Warning for PKZ856.