FXAK68 PAFC 070034 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 434 PM AKDT Sat Jul 6 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Today through Tuesday)... Widespread rainfall continues to take place over Southcentral this afternoon, with places near the Talkeetna Mountains and Gulf coast getting the heaviest rain at the moment. The heaviest rain will begin to taper off through the evening and become mostly light rain by Sunday morning. Southwesterly flow will continue through at least the early part of next week, allowing for upslope precipitation to take place along all of the western facing mountainsides. Widespread cloud cover will also continue, resulting in cooler temperatures persisting for much of the area. Another round of widespread rainfall is expected Monday afternoon as multiple shortwaves from upper lows in both the Bering and Gulf interact over southern Alaska. Locations near the Talkeetna Mountains and Alaska Range are currently expected to get the most rainfall, while lower elevation areas along the Copper River Basin could get little to no rain due to downsloping. The next event of concern will occur late Tuesday as a strong shortwave low from the Bering moves eastward into central Alaska, in addition to the upper low in the Gulf shifting northward towards the coastline. The shortwave low will move over southwest Alaska during the day on Tuesday before stalling near the Alaska Range, producing widespread heavier rain for most of that part of the state. Some spillover precipitation may take place for areas north and west of Cook Inlet, though downsloping could impact precipitation rates at lower elevations. The upper low in the Gulf will send a wave of rainfall over the coastline and into Prince William Sound midday Tuesday, lasting well into the overnight hours. While unsettled weather is expected to continue into the foreseeable future, winds across most of the area will become much calmer by Sunday morning due to the pressure gradient over Southcentral starting to weaken tonight. -BS && .SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3)... Satellite images this morning and afternoon show a trough digging into the Central Aleutians with surface observations reporting fog, low clouds and persistent north to northwest wind over the area. Tomorrow, a ridge of high pressure over the Western Aleutians begins to slightly flatten with the arrival of a Kamchatka Low in the Bering Sea. This low will bring reinforcing rain showers and low ceiling/fog conditions into tomorrow evening as the low moves south through the Aleutians. Temperatures will hold steady in the upper 50s/lower 60s today and tomorrow with lows in the 40s across the Western and Central Aleutians. Small craft wind gusts will accompany the low's track. Elsewhere today, satellite images show a cold front with rain showers over the Alaska Peninsula and portions of the Southwest. These rain showers and northerly to northeasterly moving clouds will continue through tomorrow afternoon as a result of a southerly winds from a stationary low due south of Sand Point in the North Pacific Ocean. Northerly flow over the Kuskokwim Delta and Alaska Range will continue to bring cloud cover and scattered rain showers to the area through tomorrow evening. A fast moving low from the North Bering Sea could bring a quick period of heavy rain showers Monday evening into Tuesday to the Toksook Bay-Aniak- Togiak area. -DJ && .LONG TERM FORECAST (Days 4 through 7) Wednesday through Saturday... An Arctic upper level closed low center slips through the Bering Strait and moves to the Yukon Delta by the end of the forecast period. A second low center in the Gulf of Alaska merges with this low to form a Bering-wide low, with a trough extending back through the Gulf into the Eastern North Pacific. These two systems continue to spread precipitation across the Southern Mainland and Alaska Peninsula. A weak ridge holds onto the Eastern Interior through Saturday. This helps dry out areas near the ALCAN border, but also increases the risks for development of convective activity through the week. Despite good agreements in the larger scale features throughout the forecast, forecast spread and uncertainty between models becomes problematic through the second half of the forecast period. Longer term light precipitation will cover from the Canadian border across Southwest Alaska and the AKPEN, bringing some relief with forest fires. Expect brief periods of heavier rainfall as the upper features move through the pattern into the weekend, with gusty offshore winds developing Saturday. - Kutz .AVIATION... PANC...VFR ceilings below 5,000ft will persist from late afternoon through the overnight hours. Expect additional lower cloud decks, around 2,500ft, at times throughout evening and nighttime hours as occasional showers move over the terminal. Heavier showers may bring ceilings down to this 2,500ft level (MVFR) later this afternoon. Shower activity is expected to taper off later this evening. Southeasterly Turnagain Arm winds will also persist across the terminal through Sunday morning. Sustained winds and gusts have likely already peaked, and will slowly diminish through the TAF period. Gusts of 25 to 35 mph are still likely this evening through around midnight. South winds will become light at around 10 mph by mid-morning Sunday as the frontal system finally slides south over the northern Gulf. && $$