Marine Weather and Tide Forecast for Twin Hills, AK

FXAK68 PAFC 071404 AFDAFC

Southcentral and Southwest Alaska Forecast Discussion National Weather Service Anchorage AK 504 AM AKST Sat Dec 7 2024

.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)...

Discussion:

An inverted trough extending northwest from a low in the southeastern Gulf currently sits over the Barren Islands. It will remain relatively stationary through the day before slowly lifting northeast toward Prince William Sound before dissipating Sunday.

An east-southeasterly flow aloft out ahead of the trough continues to advect moisture over the Kenai Peninsula and Cook Inlet. The result has been a wintry mix of precipitation from the Kenai Peninsula north into the Susitna Valley. Nearer the trough axis, the precipitation has been more showery in nature, with mixed rain/snow showers from Portage and Whittier over to Homer. More stratiform rain/snow/freezing rain extends from the Sterling Highway north to the Susitna Valley.

Temperatures in these locations are once again straddling the freezing mark with the coldest temperatures along the Seward Highway and western Susitna Valley. These locations are seeing the freezing rain and snow this morning with warmer locations like Homer and Kenai seeing mainly rain. Chances for mixed precipitation will persist through early Sunday morning before the trough weakens and a second, much stronger surface front moves from the western Gulf toward mainland Southcentral Alaska.

Gale force winds, with a small core of storm force winds for the Barren Islands, are expected along the front with ample moisture with this system. Again, warm southeasterly air looks to advect into Southcentral, so any locations near freezing initially will quickly warm into the 30s and 40s and snow levels again rising to 2,000 ft higher by Monday. Turnagain Arm winds will also be on the increase, as well as winds at higher elevations, including the Anchorage Hillside where gusts to 60 mph are possible beginning Sunday night.

The front then weakens, slows, and stalls near Prince William Sound on Monday. However, a strong upper-level wave moving north into the Gulf will advect more moisture toward coastal Southcentral as a second frontal boundary brings about another round of gusty winds to the coastal waters, gaps, and higher elevations of Southcentral Alaska. Upward of 2 to 3 inches of rain could fall for coastal communities from Whittier to Kodiak with lesser amounts farther east toward Cordova. For locations in the lee of the coastal mountains, a strong cross barrier flow and downsloping should limit any chance for accumulating precipitation.

-TM