Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
298 FXAK68 PAFC 130052 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 452 PM AKDT Wed Jun 12 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)... A stacked low south of Kodiak Island will slowly move east over the next few days as high pressure builds in over interior Alaska. Easterly flow with embedded shortwaves has brought precipitation across the area moving from east to west over the Copper River Basin through the Mat-Su Valley. A few pop-up showers will remain possible for the Kenai Peninsula and Anchorage areas through early tonight. Residual moisture and another shortwave descending from interior Alaska will continue scattered rain showers across the Copper River Basin on Thursday. A few isolated thunderstorms are possible across the northern portions of the Basin in the late afternoon/evening, however, instability is very marginal with ample cloud cover. Friday will mark the beginning of a warmer and overall drier period, albeit with thunderstorm potential, as a ridge builds in over Southwestern Alaska. Strong northerly offshore flow aloft on the eastern periphery of this ridge will generally bring dry conditions with warming temperatures. As temperatures also warm aloft and a few upper level shortwaves move through, atmospheric instability will build with each passing day. The potential for widely scattered thunderstorms exists for the entire Copper River Basin and possibly in the Susitna Valley on Friday as high temperature rise in the mid 60s near the immediate coast to mid 70s inland. With even more available instability and potentially an even more potent upper wave, thunderstorms will also be possible in the Anchorage and western Kenai Peninsula areas in addition to the Copper River Basin and Mat-Su Valley on Saturday. High temperatures on Saturday will rise into the 70s for most, nearing 80 for inland areas. Thunderstorm chances are likely to continue through the rest of the weekend into the beginning of next week. -ME && .SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 3)... Light rain showers will taper off this afternoon across the Kuskokwim Valley and Bristol Bay areas. A benign pattern sets up over Southwest for the rest of the week as high pressure ridging moves in. By Friday, drier air will return to Southwest Alaska, filtered south through the Western Alaska Range. By Saturday, upper-level support may provide enough energy to allow for some isolated thunderstorms to generate in the foothills of the Western Alaska Range and may move southwest into the Lower Kuskokwim Valley and Bristol Bay. A low moving in west of the Western Aleutians will push westward, along the southern edge of the Aleutian Chain through late this week, eventually stalling in the North Pacific south of Adak. This will bring rounds of rain showers and small craft winds to the Western/Central Aleutians through the end of the week. && .LONG TERM FORECAST (Days 4 through 7) Sunday through Wednesday... The upper level Mainland Alaska high gets squeezed into the Bering for Monday, and continues into the Russian Arctic by Wednesday. An Arctic low pushes across the northern half of the Interior through midweek while an elongated low stretches across the Aleutians and Bering into the Gulf of Alaska, then continues into the Canadian Provinces. Model confidence falls off somewhat through the period with variations of speed and strength of the surface elements, but overall maintains good consistency for the forecast period. Most energetic weather is expected along the Aleutians and Southern Bering. Heaviest showers and locally gusty winds begin in the Central and Eastern Aleutians and the Bering up to the Pribilofs on Sunday. Winds taper off Monday. Showers will occur across the Southcentral Interior for 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 to 70s and possible low 80s over the Eastern Interior through the period. - Kutz && .AVIATION... PANC...Expect generally light southwesterly flow and dry conditions, with VFR ceilings remaining right around 5000 ft. Vicinity rain showers this evening and overnight bring the potential for ceilings to drop below 5000 ft and perhaps even into MVFR. Otherwise, there is only a small chance (10-20%) of a stray shower moving over the terminal. Rain chances decrease heading into Thursday. - KC && $$