Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
445 FXAK68 PAFC 141322 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 522 AM AKDT Fri Jun 14 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Friday through Sunday)... The upper level pattern has now shifted to put a weak upper level ridge over Southwest mainland Alaska and the weak upper level trough over Southeast Alaska. That leaves Southcentral in northeasterly flow aloft as well as warmer temperatures due to the ridge. However, there will not be enough subsidence to prevent afternoon and evening convection which will be the main weather focus today and through the weekend. At the surface, a trough along the north Gulf coast is increasing the northerly gap winds with Seward and Whittier already seeing gusty winds. The northerly winds in Seward will also push their temperature near, if not above, 70 degrees as the trough will override their typical daily sea breeze. There should be plenty of sunshine at times throughout the day, though clouds from overnight thunderstorms in the interior are moving across the Copper River Basin early this morning and other parts of Southcentral will see them pass through for a few ours. This should not be enough to keep the temperatures from warming up to the highest of the summer so far for much of Southcentral. In fact, this should be a noticeably warmer weekend than the previous ones this summer have been. That warmth, along with the cooler air aloft, will also be a key factor in the development of showers and thunderstorms today through the weekend. The most unstable air is aloft today and it is expected that most of the showers and thunderstorms will develop over the mountains today with the western Copper River Basin and eastern Susitna Valley the most favored locations for development. For Saturday and Sunday, there will be more widespread showers and thunderstorms with a better chance for the thunderstorms to make it over Anchorage and the Kenai Peninsula as well. && .SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3)... High pressure is set up over Southwest Alaska, producing drier conditions and gradually warming temperatures. There is the potential for convective activity Saturday and Sunday afternoon, which has may produce some wet thunderstorms. Primary area for thunderstorms will be along the Western Alaska Range but may extend into portions of the lower Kuskokwim Valley and Bristol Bay. There is some mild uncertainty regarding the extent of this round of thunderstorms, namely how strong offshore flow will warm the area and advect the cells downstream off the foothills of the Western Alaska Range. Areas of patchy fog and/or low stratus are possible this morning across portions of Bristol Bay. && .LONG TERM FORECAST (Days 4 through 7) Monday through Thursday... A very active pattern on the Alaska Weather map as an upper level Arctic low spreads its influence across the North Slope into Interior Alaska through Thursday. A ridge remains across the Southern Interior, being squeezed between the Arctic low and a broad low stretching across the Aleutians and Gulf of Alaska through the period. This ridge is sufficient enough to support thermal surface troughs and raises the chances for convective activity. A number of weak perturbations are expected to slide through the pattern across the Southern portions of the state throughout the forecast. Most of the concentrated weather remains in the North Pacific to the South of the Aleutians and Alaska Peninsula. Showers and locally breezy conditions begin in the Central and Eastern Aleutians and the Bering up to the Pribilofs beginning Monday. Winds taper off late Monday. Showers will occur across the Southcentral Interior for late Monday. The Aleutians front continues its Eastward push over the Alaska Peninsula and Kodiak Island before spreading more rain over Southcentral, Prince William Sound and the Copper River Valley through midweek. Showers linger behind the front over the Aleutians and Bering. Temperatures range from the 40s across the Aleutians warming across the Mainland into the 70s and possible low 80s over the Eastern Interior through the period. Thunderstorms are possible over most of the Eastern inland areas. - Kutz && .AVIATION... PANC...VFR conditions and light winds persist through midday today. Isolated rain showers moving southward will lower ceiling heights in the afternoon and evening hours. There is a less than 10% chance of an isolated thunderstorm late this afternoon/early this evening. The chance of afternoon and evening rain showers and a 10% chance of an isolated evening thunderstorm exists for tomorrow. VFR to MVFR conditions in the late afternoon to late evening hours are likely tomorrow. && $$