textproduct: Anchorage

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)

The fog around Anchorage and the Kenai Peninsula is much less extensive this morning, but there are still areas of it, especially along Knik Arm and the interior of the Kenai. With increasing northerly flow at the surface today, this fog should largely dissipate, though there could still be some patchy fog near the front range of the Chugach and Kenai Mountains.

An upper level low in the eastern Interior extends into the Copper River Basin this morning and has brought some more widespread clouds there. This low will track westward through the day and should allow those clouds the dissipate as it leaves the area. Areas of low stratus and patchy is likely to persist, but areas that do clear out will see temperatures plunge well below zero tonight and Wednesday night.

A front is pushing into the western Gulf and across Kodiak Island today. Temperatures for Kodiak look to remain in the mid 30s to lower 40s, keeping any precipitation that falls as rain. Models have a good consensus on the timing of the front, but differ somewhat on structure and if the front can spin up a low along its trough axis. When the front likely arrives to Southcentral Wednesday afternoon/evening, cross barrier flow and downsloping in lee of the Chugach will help to keep precipitation amounts light across the Anchorage Bowl. The windward slopes, however, could see light snowfall accumulations with rain being the predominant precipitation type for the Prince William Sound. The front will then stall out along the coast as a potentially more impactful system enters the Gulf for Thursday

LONG TERM FORECAST (Days 4 through 7/Friday through Monday)

A pattern shift to warmer temperatures and precipitation continues to be seen in the long range models.

A ridge builds in the Pacific Ocean and slowly moves eastward through the weekend. On Friday and Saturday, its orientation in the Pacific Ocean results in southerly flow into the Aleutians and a more southwesterly flow into Kodiak Island and Southcentral. This brings warm air advection for the Aleutians resulting in weekend precipitation falling as mostly rain and strong southerly winds; especially through the bays and passes. While a main low rotates well east of the Pribilofs in the Bering Sea this weekend, numerous lows move over the Aleutians bringing periods of heavy rainfall and winds to the area. As the high moves eastward Sunday/Monday, the chances of storms reaching the Mainland increases though confidence in their exact location and strength through the Bering Sea is low at this time.

Southwesterly flow into Kodiak Island and Southcentral Alaska persists this weekend with the greatest chance of precipitation late Saturday into Monday. Right now, mesoscale disagreement remains for timing and amounts of the heaviest precipitation from weak lows moving through from the Pacific Ocean into the Gulf of Alaska. However, this synoptic pattern indicates a warming trend for Kodiak Island and Southcentral this weekend and into Prince William Sound Monday as waves of moisture bring periods of periods of heavy precipitation and gusty winds with warm air advection to the region.

-Johnston

AVIATION

PANC... Low stratus and patchy fog continue to be stubborn this morning. However, unlike the past few mornings, visibilities are not expected to be sustained 1/2 to 1/4 mile but rather more like 2 to 5 miles with isolated instances below 1 mile. Visibilities will bounce around between VFR and IFR as patchy fog moves in and out of the terminal this morning. Predominant VFR conditions should return by late morning today. In addition, a weak front will lift northward through the Gulf today with flow increasing in the middle to upper levels out of the south and southeast with surface winds increasing out of the north this evening. This should result in VFR conditions with the fog fully dissipated around the terminal.