textproduct: Anchorage

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)

Conditions overnight have been rather quiet across much of Southcentral in the wake of the storm system that moved through the region yesterday. Scattered clouds are lingering across the area; however, there are a few breaks allowing for both temperatures to fall into the teens and 20s and areas of fog to develop, especially across Cook Inlet and around Homer.

Over the Gulf, the weather pattern is a bit more complex, dominated by three distinct areas of low pressure - one moving east to west across the northern Gulf, another over the southern Gulf, and the third situated along the coast of the Alaska Panhandle. The first of these features will continue to strengthen today as it moves to an area south of Seward later this morning. This low is then expected to lift north with its associated upper- level shortwave, although the exact track and timing of this northward jog remain quite uncertain due to extensive model spread. Even with this uncertainty, there is high confidence that this feature will bring another round of coastal rain and mountain snow along with gusty easterly winds for the northern Gulf and Prince William Sound areas for Wednesday. Some precipitation is likely to spill over the coastal mountains as well; however, the extent of this will be determined by low track and winds aloft. It is likely that a dry northerly flow near the surface, similar to the previous weather system, may help minimize the amount of precipitation that does fall from the western Kenai Peninsula through the Matanuska Valley late Wednesday into Thursday morning.

To complicate matters further, there is still a slight warm nose of air aloft out ahead of this system. While low confidence at this time, the warmer air aloft may allow for a slight chance (20-30%) of freezing rain (mainly freezing sprinkles) before colder air works in along with any steadier precipitation allowing the precipitation to fall as snow by early Thursday morning. That said, any snow that does fall will likely be very light, with only a dusting to up to an inch possible in these locations. The heaviest snow and highest totals will again be across the eastern Kenai and mainly at elevation with areas from Turnagain Pass to Tern Lake likely (60-70%) seeing up to 4 inches of snow.

The southeasterly flow will also allow for additional moisture to move into Prince William Sound through late Thursday as the other two surface lows lift north and west in the wake of the first. This will keep conditions along the coast unsettled through Thursday night before a transient ridge helps to dry things out for a bit on Friday. However, another round of precipitation may move into the coast by late Friday as the ridge lifts north and a southerly flow off the Gulf develops.

-TM

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

Friday starts with less active weather across Southwest and Southcentral Alaska as weak ridging builds over the Bering and weak features move the Alaska mainland. Cold air advection drops into Southwest Alaska, allowing for scattered snow showers. The northerly flow will allow for small craft level gap winds in the Eastern Aleutians and Alaska Peninsula areas and scattered showers over much of the Bering. Also, another low moves into the Shemya area from the west, bringing another round of gusty winds and rainfall.

Saturday sees this low move further into the Bering, allowing for the low's front to progress and bring rain to much of the Aleutians. Gusty winds also will impact the Aleutians with the front. Meanwhile, Southcentral sees a low move south of the Gulf of Alaska, turning winds more northwesterly along Kodiak Island and allowing for gap winds in the waters around the island. There is much uncertainty on Sunday in the Bering with regards to the low track. It will progress eastward, but it is uncertain where it will track to. However, whichever track it takes should still bring rain and snow to the Southwest Mainland and gusty winds along the Aleutians. Southcentral is still uncertain at this point with many low level features moving through and bringing rain/snow and elevated winds wherever they move. Monday is even more uncertain with a ridge building somewhere in the Bering and a low moving into the Gulf of Alaska. However, the exact track of these features and their impacts is too uncertain to be clarified at this moment.

-JAR

AVIATION

PANC....VFR conditions are expected through today and into the evening, with mostly clear skies and light northerly winds around 7 kt. Winds will gradually increase Wednesday evening, with ceilings lowering overnight as precipitation approaches.

A mix of of light rain and snow is expected to develop around 9 PM Wednesday, with ceilings lowering to around 4000 ft. Northerly winds will slightly increase to 11 kt after midnight, with light rain and snow continuing along with mist reducing visibility to around 6 SM. Ceilings will lower further to around 3000 ft early Thursday morning, with MVFR conditions possible toward the end of the TAF period.

-LM