Area Forecast Discussion
Issued by NWS Anchorage, AK

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000 FXAK68 PAFC 021350 AFDAFC Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 450 AM AKST Tue Mar 2 2021 .ANALYSIS AND UPPER LEVELS... Satellite imagery shows a weakening vertically stacked, complex low residing over the eastern Bering this morning, keeping the an active pattern stretched across the region. On the backside of this system, strong winds persists from the Pribilofs to the eastern Aleutians and AKPEN, which has dropped the visibility at times during periods of light snow. Over the Southwest mainland, snow showers continue as the front with the aforementioned low pushes farther inland. Snow has already started to taper off over the Kuskokwim Delta and will continue to weaken from west to east. Across Southcentral, a compact low is lifting into the North Gulf Coast. Relatively quiet conditions remain across the region as the northerly offshore pattern begins to set up. && .MODEL DISCUSSION... Models remain in good consensus with the active weather pattern across the Bering and mainland Alaska over the next few days. Thus, forecast confidence remains above average. && .AVIATION... PANC...MVFR conditions are possible early this morning, which will gradually improve to VFR with light winds by the afternoon. Fog and low stratus could develop Tuesday evening across Cook Inlet and at the airport. && .SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 and 2: Today through Wednesday Night)... For most of Southcentral, the weather will be much quieter today, and the quiet weather will persist through Wednesday night. Light snow continues this morning in Cordova and points east, as the low that greatly assisted in causing the snow area-wide yesterday moves into the coastal Chugach and rapidly dissipates. Lingering moisture may cause light snow shower activity to persist throughout the day today in the Cordova area. Elsewhere, low cloud cover is over much of Southcentral, however, most of it is not producing precipitation. The cloud cover should slowly diminish through today with solar heating. The weak surface low/troughing over Southwest Alaska will shift east and consolidate into a low over the eastern Gulf by Wednesday morning. This will allow a renewed surge of Arctic air to move southward across Southcentral by Wednesday. In addition to falling temperatures, the most significant impact will be strengthening winds and freezing spray potential across all of the coastal waters north of Kodiak Island by Wednesday night. This surge of colder, drier air should result in continued dissipation of any remaining cloud cover. However, the resulting atmospheric inversion may support some limited freezing fog generation, especially in the upper Cook Inlet and the Arms. Even in these areas, the fog tonight is not expected to be dense due to the otherwise dry air mass around. Looking ahead, the next round of inland and mountain snow with coastal rain/mix remains on track starting Thursday night, and may persist into Saturday. This feature is looking more substantial as compared with 24 hours ago, but the details that will determine how much accumulation occurs remain highly uncertain. && .SHORT TERM FORECAST SOUTHWEST ALASKA (Days 1 through 2)... A broad surface low in the eastern Bering will continue to influence the sensible weather across Southwest Alaska today. Remnant moisture embedded in cyclonic flow will produce more showers today for portions of Southwest Alaska. As the low pushes south today, northerly flow will set up for most of the region. There will be a break between systems on Wednesday. Thursday the next Bering front will push inland bringing yet another batch of snow to the K-Delta, Bethel, Dillingham and King Salmon. && .SHORT TERM FORECAST BERING SEA/ALEUTIANS (Days 1 through 2)... The remnants of a low over the Bering continues to yield snow showers, gusty conditions, and enhanced seas. The surface low will move out of the Eastern Bering and south of the Alaska Peninsula this afternoon. In its wake, northerly flow and a tight pressure gradient from the Pribilof Islands to Port Heiden. By Wednesday morning there will be a weak ridge over Atka and St. Paul. Additionally, there is a new surface low over Kamchatka with a surface pressure of 967 mb and the front at the door set of Attu Island. This front will rapidly push across the Aleutians Wednesday and early Thursday bringing another round of unsettled weather. && .MARINE (Days 3 through 5: Thursday through Saturday)... Bering: A well developed front moves into Western Alaska for Fri. Forecast confidence is good. Widespread high end southerly gale force winds and waves with areas of storm force gusts moves with the front. Waves building to 20 feet Fri. The associated well developed low and trailing front move across the Bering from the West through Fri, and brings widespread high end westerly gale force winds across the Aleutians/Bering through Sat. Waves building to 35 feet over the Central Bering subsiding to mid-20s over the remainder of the area through Sat. Gulf of Alaska: A low slowly exits the Southern Gulf Fri, with outflow small craft winds off the Alaska Peninsula from the Barren Islands to the Shumagin Islands right behind. Models vary, but confidence is good. A new low and front move across the Gulf through Sat, bringing widespread southeasterly winds with the front through Fri. Northwest small craft winds with areas if gale force gusts follow after frontal passage Sat. Waves building to 12 feet across the Southern Gulf, subsiding Sat. && .LONG TERM FORECAST (Days 4 through 7: Friday through Monday)... Active weather is expected to makes its return to southern Alaska during the forecast period with the details of each individual system uncertain at this time. Model guidance keeps a rather strong Arctic/Siberian upper level low over northeast Russia while upper level ridging tries to push northward along the Alaska Peninsula into Southcentral and Southeast Alaska. The storm track will basically be from the western Bering eastward along the Aleutian Chain to Kodiak Island and then to somewhere near Prince William Sound as these ride the eastern periphery of the deep cold Arctic/Siberian air over northeast Russia. Overall, expect a milder pattern to ensue for this time period with temperatures still slightly below normal but closer to the normal values of where they typically are this time of the year which is near 32 degrees F for Anchorage. This pattern could potentially mean a snowier regime for Southcentral and in particular across the Anchorage Bowl. However, many factors have to come together for Anchorage to get the snow, though, the storm track looks favorable with model guidance mostly bringing lows near and into Prince William Sound with details of each uncertain. && .AFC WATCHES/WARNINGS/ADVISORIES... PUBLIC...Blizzard Warning 185 195 Winter Weather Advisory 155 181 High Wind Warning 185 MARINE...Storm Warning 170 178 411 Gales 130 131 150 155 160 165 171-77 179 180 185 412 413 414 Heavy Freezing Spray 160 165 179 180 185 412 414 FIRE WEATHER...NONE. && $$ SYNOPSIS AND MODEL DISCUSSION...ALH SOUTHCENTRAL ALASKA...JPW SOUTHWEST ALASKA/BERING SEA/ALEUTIANS...PJS MARINE/LONG TERM...MK/MV

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