Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
914 FXAK68 PAFC 250226 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 626 PM AKDT Mon Aug 24 2026 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3/ Today through Thursday)... Key Message: - Special Weather Statement has been issued for strong winds tomorrow, Tuesday for Anchorage, Anchorage Hillside, Palmer and Butte. Discussion: A brief period of relatively quiet weather continues across much of Southcentral today as an upper-level ridge shifts eastward across the region. However, this break will be short-lived as a potent shortwave trough approaches from the southwest tonight into Tuesday. Increasing southwesterly flow aloft ahead of the trough will transport a plume of moisture into Southcentral, with rain initially developing across the Susitna valley before becoming more widespread Tuesday evening. The shortwave takes on a negatively tilted orientation as it lifts northeast across Southcentral on Tuesday, providing stronger upper-level forcing as the associated front pushes inland. Widespread rain is expected across much of the region, with the greatest rainfall amount favored across the northern and eastern Susitna Valley where persistent southerly flow will enhance upslope precipitation along the Talkeetna Mountains and Alaska Range. Meanwhile, downslope flow will likely result in lower rainfall amounts for portions of the western Kenai Peninsula and Anchorage. Winds will also become a significant component of Tuesday`s system as the pressure gradient tightens considerably across Southcentral. Strong southeasterly gap winds are expected through Turnagain Arm and the higher terrain surrounding Anchorage, with winds spilling into the Anchorage Hillside. Gusts around 40 kt are possible across portions of Anchorage, including the airport, particularly Tuesday afternoon and early evening. Strong winds are also expected through the Knik Valley and Copper River Basin gaps as the front moves through. The shortwave and associated surface front lift north and east Tuesday night into Wednesday, allowing widespread precipitation to gradually diminish from west to east. lingering showers remain possible Wednesday, particularly along the mountains, as a trailing upper-level disturbance crosses the region. Otherwise, conditions trend quieter through the day as weak ridging begins to build back across Southcentral. This respite looks relatively brief, however, as the upper-level pattern remains progressive and another trough approaches Alaska from the west heading toward the latter half of the week. LM && .SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3: This afternoon through Thursday evening)... Afternoon satellite imagery reveals a trough stretching across Siberia and into the Bering Sea. A surface low continues to move through the Chukchi Sea as its front is currently over interior Alaska and interior Southwest Alaska. Rain will continue across Southwest through Tuesday as the base of the trough continues to move across the northern and central Bering. Most rain on Tuesday will fall along the terrain which will be aided by westerly upslope flow. Steady rain Tuesday morning tapers off to showers Tuesday afternoon and evening as the main trough axis and steady rain moves east to Southcentral. Wednesday will see drier and quieter weather before the next Bering system moves in for Thursday. Speaking of the next Bering system, it will begin to gather Tuesday afternoon as upper-level North Pacific energy interacts with an upper-level over Kamchatka. This interaction will help deepen a surface low between Kamchatka and the Western Aleutians. Warm, moist, tropical air will ride northward from the Pacific and into the Bering Sea beginning Wednesday. At atmospheric river will also accompany this system as moderate to heavy rain moves into Shemya Wednesday morning. The heavy rain axis shifts east by Wednesday afternoon and evening as rain moves into the Pribilof Islands by then. Moderate to heavy rain then moves into Southwest starting with the Kuskokwim Delta Coast by Thursday morning and advances inland across the rest of Southwest through Thursday afternoon and evening. Gale-force southerly to southwesterly winds are likely (60 to 70% chance) across the western Bering Wednesday and advancing across the Bering to the eastern Bering and Kuskokwim Bay by Thursday afternoon and evening. There is little threat with coastal flooding (10% or less) along the Kuskokwim Delta Coast with this system due to the lower tide cycle the area is currently in. There will still be rough seas just off the coast with wave heights approaching 8 feet by Thursday evening. Gusty winds will make it inland of the Kuskokwim Delta Coast where locations such as Bethel will contend with gusty conditions with ongoing moderate to heavy rain. Stay tuned for forecast updates regarding the evolution of this next Bering system. && .LONG TERM FORECAST (Days 4 through 7: Friday through Monday)... An active, progressive pattern continues through the end of the week and into early next week as multiple systems quickly track from west to east. This will generally bring periods of active weather, with brief lulls in between for most locations. By Friday morning, a 990 mb low will have tracked just east of St. Laurence Island and begins to move inland near the Norton Sound, bringing moderate to heavy precipitation across much of southwestern Alaska. Concurrently, southwesterly small-craft to gale- force winds will continue to push into Bristol Bay and the Kuskokwim Delta coast. Widespread precipitation will also filter into Southcentral, and will be particularly heavy for the northern Gulf coast and Talkeetna Mountains. Turnagain/Knik gaps winds will likely return Friday, bringing potential for gusty conditions around Anchorage and Palmer. River levels across the Susitna Valley, such as the Yentna River at Lake Creek will have to be monitored closely with this system for potential flooding concerns. By Saturday morning, the trough ejects a surface low into the Gulf, causing rainfall to taper off from west to east across the mainland as this low continues toward the Alaskan Panhandle. Some showers may linger in spots, particularly for Prince William Sound and the western/central Chugach, though conditions will gradually improve as ridging rebuilds over the region. A separate North Pacific low moves into the western bering by Saturday which will likely bring another wave of precipitation to the western/central Aleutians. Deterministic solutions begin to differ substantially by Monday. However, ensemble means show a broad ridge amplifying just south of the Aleutians, which could set up a period of moist flow. Another shortwave appears to work down the mainland by Monday. If this feature can tap into this moisture, another round of widespread precipitation could be on track for much of the southern Alaska early next week. -CW && .AVIATION... PANC...Clouds will be on the increase this afternoon and evening as a frontal system advances toward the terminal from the west. VFR conditions will persist through tonight, although light rain is expected to develop by this evening. A southeasterly Turnagain Arm wind will develop overnight with these winds beginning to move over the terminal by early Tuesday morning. Sustained winds of 15 to 30 mph are likely along with gusts up to 40 mph. Occasional gusts of 45 to 50 mph are possible ( 30-40%) during the peak of the wind event, likely between 8 AM and 6 PM. Any heavier rainfall should hold off through the first half of Tuesday due to the these winds. However, steadier rain is expected by late Tuesday afternoon as the winds begin to diminish and the front moves into the area. MFVR cigs and vis are expected with this round of steady rainfall. There is a low chance ( 10-20%) that ceilings may fall to IFR in the wake of this system overnight Tuesday into early Wednesday morning as the wind flow aloft weakens. && $$