textproduct: Anchorage

SHORT TERM FORECAST SOUTHCENTRAL ALASKA (Days 1 through 3)

A shortwave rounding the base of a broad upper level trough over the Bering will move east into the southern Mainland today. Southwesterly flow aloft and a shortwave lifting into Southcentral will spread light snow over the western Alaska Range and into the Susitna Valley late this evening. Colder air will stream into the region as well, with the leading shortwave driving quickly into the eastern Gulf by early Sunday morning. With a lee-side low developing and a negatively tilted trough taking shape, widespread snow will fill in quickly across Southcentral early Sunday morning. Forecast confidence is high for accumulating snow Sunday morning due to colder air in place aloft and precipitation starting prior to sunrise. As temperatures rise through the day, snow will likely begin to melt on roadways and accumulation will become limited for the lower elevations. Higher elevations however, may continue to see accumulation through the afternoon and into Sunday night. The Mat-Su Valleys are more likely to switch over to a mix or rain due to some downslope warming off of the Alaska Range and Talkeetnas as flow aloft becomes northwesterly in the afternoon and evening. At this time however, the Anchorage and Eagle River Hillsides may get higher snowfall rates as upslope flow really kicks in on the western Chugach. The main uncertainty is whether or not the precipitation is more over the high peaks or low enough to impact the road network.

Moving into Monday, the Copper Valley will continue to receive some light precipitation, mainly over the mountains and the southern Valley as the upper low swings into southwest Yukon Territory. Heading into Tuesday, ridging will redevelop and precipitation will come to an end.

Of note with this storm as well will be the winds for Kodiak, southern Kachemak Bay, and the Barren Islands starting Sunday afternoon and continuing through Monday. The decent cold air push and strong shortwave will bring widespread gales to these areas.

AVIATION

PANC...The morning hours are still vulnerable to IFR to MVFR conditions mainly due to stratus and fog, but there should be improvement to VFR conditions as the day warms. Snow is expected to move over the terminal Saturday night into Sunday, bringing periods of reduced visibility and potential for MVFR conditions.