textproduct: Fairbanks

SYNOPSIS

Widespread winter weather and blizzard conditions have calmed down early this morning across much of Northern Alaska, therefore the majority of the posted hazards were allowed to expire early. Blizzard conditions persist across the far western Seward Peninsula to St Lawrence Island this morning before tapering off from east to west through the day. Relatively dry conditions expected today for the Interior and Arctic coast. Winds have diminished through the Alaska range passes, but another shortwave should increase southerly winds there late tonight into Sunday, remaining below warning criteria. Another round of light snow traverses the state from west to east, beginning in the YK Delta and West Coast late tonight shifting into the Interior Sunday and Sunday night.

KEY WEATHER MESSAGES

Central and Eastern Interior...

- Winter storm conditions have largely come to an end, much drier day expected for the Interior with highs in the 20s and 30s.

- Southerly gap winds across the Alaska range passes have decreased, but expect them to increase again late this afternoon into Sunday

- Light snow overspreads the Interior from west to east Sunday with only minor accumulations possible

West Coast and Western Interior...

- Blizzard conditions continue early today for the western Seward peninsula, diminishing through the afternoon as the main axis of snow moves west. Worst conditions persisting for St. Lawrence Island into this evening possibly.

- Breezy conditions along the west coast this morning diminish through the day

- Another round of light rain and snow pushes in from the southwest tonight before shifting into the interior on Sunday. High temperatures near or above freezing into mid next week.

North Slope and Brooks Range...

- Snow diminishing across the Brooks range this morning

- Improving conditions and diminishing winds across the Arctic coast today

- Much warmer temperatures with highs in the 20s and 30s above Sunday and Monday, but expect increasing westerly winds.

FORECAST ANALYSIS AND DISCUSSION

Satellite imagery this morning shows a low in the Bering with a fetch of moisture stretching from the Central Pacific to the Seward Peninsula while another weaker upper shortwave and associated fetch push into Southern Alaska. Relatively quiet conditions exist across Northern Alaska this morning as ridging builds in overhead, with the far west being an exception. The system in the Bering retrogrades toward Russia today as ridging nudges westward, cutting off the main fetch of moisture and working to end winter storm conditions. As ridging builds in over the state, flow briefly becomes southwesterly this evening and tomorrow with the occluding low in the Bering pushing an upper level frontal boundary eastward across Alaska. Southwesterly moisture advection and the incoming front produce additional light rain/snow showers across the west coast tonight then spread eastward through the interior on Sunday. The main threat for any P-type issues and rain should be confined to the YK Delta where surface temperatures are near or above freezing as a much warmer airmass remains in place. Snow amounts should be fairly light this weekend under a few inches. Heaviest snow showers expected along southern facing slopes in the Brooks Range and on the Seward Peninsula as orographic lifting and steeper lapse rates aloft enhance lift and snowfall rates. Much lighter snow showers spread into the eastern Interior Sunday evening, but overall little to no concern with these.

The previously mentioned weak shortwave moving into the Southern Coast of the state brings additional precipitation into the Alaska range, however downsloping winds keep areas to the north dry. The main impact with this system will be an increase in southerly winds through the passes again this evening into Sunday. This system is relatively weak compared to the previous one with winds likely remaining under warning criteria in the passes. Downsloping within this warmer airmass will likely bring temperatures above freezing and potentially nearing the 40 degree mark the next several days in areas just north of the Alaska range where the downsloping effect is greatest.

The most noticeable weather change over the next several days should be the widespread warmer temperatures across the majority of Northern Alaska. The frontal boundary pushing through on Sunday helps usher in an even warmer airmass with strong 500mb ridging nearing 570dm...a type of ridge more common in the warmer months... becoming centered over the state. Highs today reach the 30s across the west and Alaska range today. The warmer airmass engulfs the rest of the state by tomorrow with highs nearing freezing even on the North Slope.

EXTENDED FORECAST DAYS 4-7

The extended period begins with an anomalously strong ridge centered over the state bringing a welcomed mid winter thaw to almost all of Northern Alaska. The warmer airmass remains in place through midweek with the west coast staying warmer into the weekend as the ridge axis shifts westward toward the Bering. Will have to watch how guidance handles this pattern as there is consensus among longer range guidance and ensembles that the ridge remains strong and continues moving west into Siberia while troughing over Northwest Canada pushes westward into Alaska. This set up supports an arctic airmass slowly advecting back into the Interior by the end of next week resulting in another cool down. Confidence is increasing in another period of widespread below zero temperatures by the end of the period into the following week, but lower confidence still exists on finer details such as extent of the cold and timing. For now, the longer range forecast shows a slow cool down into next weekend with temperatures back into the 0 to -20 range going into the following week. The extended period will be much drier for Northern Alaska with little to no precipitation in the extended.

Coastal Hazard Potential Days 3 and 4...None

AFG WATCHES/WARNINGS/ADVISORIES

AK...Blizzard Warning for AKZ820-821-827. PK...Gale Warning for PKZ801-802-850-851-854. Brisk Wind Advisory for PKZ803-812-857-858. Brisk Wind Advisory for PKZ804. Brisk Wind Advisory for PKZ805. Brisk Wind Advisory for PKZ806-811-817. Brisk Wind Advisory for PKZ807. Brisk Wind Advisory for PKZ809. Brisk Wind Advisory for PKZ810. Brisk Wind Advisory for PKZ816. Brisk Wind Advisory for PKZ852. Brisk Wind Advisory for PKZ853. Brisk Wind Advisory for PKZ855. Brisk Wind Advisory for PKZ856.