Area Forecast Discussion
Issued by NWS Anchorage, AK
Issued by NWS Anchorage, AK
040 FXAK68 PAFC 211239 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 439 AM AKDT Sat Sep 21 2024 .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3: Today through Monday)... This morning`s weather map has that persistent upper level trough still extending out of the Interior and over the Talkeetna Mountains and southward to Prince WIlliam Sound, not unlike where it was yesterday morning. A difference today is that other are no other waves around to kick off any light showers. Lower elevations have mostly cleared out overnight, but this pesky trough is just enough to keep some mid-level clouds over the Talkeetna Mountains and packed up bear the Chugach and Kenai Mountains as well. This has limited the cooling overnight and kept Anchorage and the Matanuska Valley in particular warmer. Still expect these clouds to mostly dissipate today as that trough moves eastward and weak ridging move in from the west. All this should combine for a rather nice day for Southcentral. That starts to change Sunday as the next low plows toward the Gulf and brings rain into Kodiak by early Sunday morning and increases winds around the Gulf. While most of the marine winds around the Gulf should remain at Gale force, there is a chance for storm force winds in barrier jets right along the north Gulf coastline Sunday evening and Sunday night. This low will then rapidly weaken on Monday as it moves int the northwest part Gulf. It then remain there as the upper level trough from the Arctic starts to phase up with this low and solidify Southern Alaska in yet another upper level trough that wants to remain seemingly forever. && .SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (Days 1 through 3)... Dry and cool conditions will continue across much of Southwest Alaska through the weekend. Some light rain is expected to work its way up the Alaska Peninsula and into the southern portions of Bristol Bay on Sunday with the next front. Precipitation should clear out by Sunday night as the front tracks into the Gulf of Alaska. Some wrap around precipitation may spill over the Western Alaska Range, however, mostly dry and cool conditions will roll over into early next week. Overnight low temperatures will drop into the low to mid 30s for much of the region through early next week, with daytime temperatures in the mid 40`s. As has been advertised, active weather is beginning to move through the Aleutians with the first of two upper lows moved into the Central Aleutians yesterday afternoon and has spent the night fizzling into an open wave. A second and stronger low absorbs yesterdays system and slides over the Central Aleutians before tracking east towards the AKPen. Gale force winds will pick up across the AKPen and southeastern Bering Sea by Sunday morning. Gusty winds will wrap around the backside and pushing near gale force gusts over the Eastern Aleutians by Sunday afternoon. The consolidation of the low on Sunday and a developing pressure gradient over the Western Alaska Range into Bristol Bay will result in gusty gap winds. Gusty easterly winds of 35 to 45 mph are forecast to spill through the Kamishak Gap into portions of Greater Bristol Bay while 35 to 45 knot gusts are expected to encompass much of the Alaska Peninsula into Sunday night. Low pressure departs the region early next week. && .LONG TERM FORECAST (Days 4 through 7: Tuesday through Friday)... Long wave upper level low pressure system over much of the State continues to be the main focus in the extended outlook. Models are in fairly good agreement with a well defined surface low and upper level troughing across most of the southern portion of the State, Aleutians Islands and and Gulf waters early in the period. Models differ somewhat on intensity of shortwave troughs developing across the southern portion of the Bering Sea, Aleutian Islands and coastal Gulf of Alaska throughout the period. The long wave trough axis will remain fairly entrenched across the interior of the state, allowing for quickly moving shortwaves to bring strong coastal winds and moderate precipitation across the eastern portion of the Aleutians, the Alaskan Peninsula and coastal Gulf waters through Friday. High pressure will ridge in behind the long wave trough late Thursday and into Friday ahead of another North Pacific Low that will approach the Western Aleutians Friday evening. && .AVIATION... PANC...VFR conditions and Light winds are expected to persist. The is a slight chance for some fog to develop near the airport early this morning if the mid-level clouds clear out before mid-morning. && $$