Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
736 FXAK68 PAFC 070039 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 439 PM AKDT Thu Jun 6 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/Today through Saturday night)... An upper-level trough centered over the southern Bering Sea today continues to serve as the main driver for weather across Southern Alaska, spinning shortwaves through our area. This afternoon saw the development of continued rainfall across Prince William Sound coastline, as well as several thunderstorms develop in the Susitna Valley. Going into tonight, thunderstorm activity will begin to diminish beginning in the early evening, coming to an end tonight. Similarly, the trough pushing rainfall and gusty winds into Prince William Sound and through it`s gaps will begin to weaken and diminish by Friday morning, coming to an end by Friday afternoon. Mainland Southcentral will see a general shift towards warmer and calmer weather. By Friday afternoon, mainland Southcentral is expected to seeing some clear skies, and by Saturday afternoon, the highest temperatures of the season so far are possible, with much reaching 70 degrees in the afternoon. Coastal Southcentral however, near Prince William Sound and the southern Kenai Peninsula, are expected to see a return to cloudier and rainy conditions as early as Saturday evening due to a shortwave pushing up from the central Gulf of Alaska. Saturday will also likely not be as sunny as Friday due to clouds spilling over across the area from our system to the South. A focus of the forecast for the next few days will be for Kodiak Island as a series of shortwaves approach and sit over the area bringing continued moderate rainfall with periods of heavy rainfall beginning Friday afternoon. This system has the potential for to create a prolonged rainy pattern for Kodiak Island, continuing at least through the weekend, potentially into early next week. For Kodiak City, 2 to 4 inches of rainfall is possible over the course of Friday afternoon until Sunday afternoon. -CL && SHORT TERM FORECAST SOUTHWEST ALASKA, THE BERING SEA AND THE ALEUTIANS (Days 1 through 3: This afternoon through Sunday afternoon)... Unsettled weather continues through the weekend. A broad, upper low currently near the Eastern Aleutians will serve as a focal point, with upper level shortwaves rotating around it and driving weather across the region through Saturday. By Saturday afternoon, it merges with an approaching low from the North Pacific and moves southeastwards towards the Gulf of Alaska. Some minor uncertainty persists with the timing and magnitude of winds and precipitation as models attempt to hone in on weaker surface lows associated with this upper low. Here are the hazards/notable weather currently being monitored: * Slight chance for thunderstorms in the Lower to Middle Kuskokwim Valley (near Lime Village, Stony River, and Sleetmute) through this evening. * Periods of moderate to heavy rain (with storm totals hovering around 0.5 to 1 inch) likely on the Pacific side of the Alaska Peninsula as several waves of precipitation move in through the weekend. * Several rounds of gusty east-to-southeast winds, with gusts as high as 40-50 mph, for interior Bristol Bay through the weekend. * Daytime highs climb into the high 60s and low 70s this weekend for communities along Kuskokwim River. -KC && .LONG TERM FORECAST (Days 4 through 7) Monday through Thursday... A couple of significant changes over the Alaska Weather Map through Thursday. A Rex block builds from the Arctic into Mainland Alaska through the period. This continues to support surface thermal troughs over the Eastern Interior. One closed low wobbles over the Gulf of Alaska and the Eastern North Pacific as it weakens. A low center entering the Western Bering slips along the Aleutians and merges with the Gulf low for Wednesday. With a ridge forming over the Kamchatka and Chukotsk Peninsula, a third center from the North Pacific with its front enters the pattern over the Central Aleutians on Thursday. A blend of Canadian/ECMWF/GFS and UKMET carries good confidence for the first half of the forecast, with the EC and GFS straying from the group by the end of the forecast. The Gulf low aloft links up with a well developed surface system for Monday and Tuesday. Locally heavy rainfall is expected across coastal Southcentral Alaska, with the highest amounts along the Eastern Kenai, Kodiak Island and parts of the Alaska Peninsula for the beginning of the week. Gusty winds less than gale force will occur along the North Gulf Coast, with gale force winds through the Barren Islands and Shelikof Strait for Monday, diminishing early Tuesday. Lesser amounts of rainfall moves inland to the Alaska Range, and along the West Coast down to Bristol Bay. The Aleutians and Bering will continue rain showers, with locally gusty winds across the Central Aleutians through Tuesday. Another area of gusty winds moves across the Pribilofs through Wednesday. Another area of locally heavy rainfall comes in over the Western and Central Aleutians with a low and its front late Wednesday into Thursday, spreading East through the week. -Kutz && .AVIATION... PANC...VFR conditions will persist throughout the TAF period. A surface trough will continue to move northwest across the Kenai Peninsula and into the Susitna Valley through this evening. Turnagain Arm winds bending back over the terminal will continue to increase into the evening with peak gusts approaching 30 kts. These winds will diminish quickly by late evening, becoming light and variable overnight. An isolated shower is still possible through late afternoon; however, any reduction to ceiling and visibility with is not anticipated. Turnagain Arm winds are expected to bend back over the terminal by around noon again tomorrow. Wind gusts tomorrow afternoon are not expected to be nearly as strong as today, though. && $$