textproduct: Anchorage

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)

Discussion:

Southcentral Alaska remains in an active weather pattern with a front extending out of the North Pacific through the region this morning. This front is bringing in warmth and moisture as it originates near 30N 180. In spite of the moisture, rainfall amounts have been limited by cross-barrier flow downsloping the precipitation. Precipitation type at lower elevations has been rain with the mixed precipitation and snow being in the northern reaches of the Susitna Valley and Copper River Basin. Saturday evening saw some freezing rain around Talkeetna that led to a winter weather advisory. Temperatures have edged up overnight in the warm advection in southerly flow and changed the precipitation in Talkeetna to rain. There is a possibility for some freezing rain near Willow with temperatures right at freezing, but that is not expected to last long should it occur with temperatures expected to rise above freezing around Willow soon. North of Talkeetna, there remains a winter weather advisory for snow until this afternoon. Those areas close to the Alaska Range are seeing temperatures remain below freezing leading to a long duration snowfall expected to result in anywhere between 4 and 12 inches (highest amounts toward Broad Pass) before it all ends.

Forecast challenges this morning start with the winds coming across the Chugach Range and through Turnagain Arm. The pattern favors the Turnagain Arm wind to bend into Anchorage, especially south and west Anchorage. So far this has not happened except for an occasional gust as the Turnagain Arm jet has remained south of Anchorage. Notably, when Anchorage International airport has had that occasional gust, the temperature has spiked. The high temperature for yesterday (Saturday) at the airport was 44 as one of these gusts blew through for just a few minutes. Before (and after) this one brief gust of wind, the temperature had only reached 38. That 6 degree spike shows the warmer air just off the surface and what is moving through Turnagain Arm and why most of the precipitation has been rain across the region. This front should move east of Cook Inlet by early afternoon resulting with the rain ending. There will still be some snow upsloping in southerly flow over the Alaska Range so the northern Susitna Valley is expected to hang onto the snow until mid afternoon. Another short wave will move through the area Sunday night. This wave is not expected to bring a lot of precipitation, but the farther north one goes the better the precipitation chances. therefore the northern Susitna Valley is looking at another shot for some snow again late this evening into Monday morning.

Conditions start to dry out by Monday afternoon as a ridge moves into the region for Tuesday and Wednesday.

AVIATION

PANC...Southerly wind gusts 20 to 25 knots will continue through this morning, breaking briefly this afternoon before increasing again by 06Z today. Light rain expected over the terminal this morning with cloud ceilings dropping below 5000 ft. Ceilings will drop further to MVFR this afternoon before rising again after 06Z. Low level wind shear possible through 15Z this morning.