A potent weekend storm is lingering along the Alcan and Panhandle with a couple of inches of snow likely for areas of the northern Panhandle. This storm brought nine to 18 inches of snow to Anchorage and 18 inches to Valdez. Rain fell on several feet of snow in Cordova, saturating it and increasing its weight substantially. Heavy wet snow on buildings will pose a threat to life and property this week.
All attention now turns to what is to come. Another major low-pressure system is located south of the Aleutians and is moving northeast toward Southcentral. Central pressure will bottom out at 968 millibars. The low is associated with a strong upper jet.
This jet is an extremely important player in the forecast with this storm. Models indicate that it will steer rich subtropical moisture into Prince William Sound Monday night and Tuesday, before pushing to the east. In Cordova, snow will become heavy overnight. As temperatures climb tomorrow, precipitation will gradually change to all rain. Rain is also likely Tuesday night and Wednesday. Colder air will filter back into the area and could change rain back to snow before conditions improve by Friday.Up to a foot of snow is possible in Cordova, followed by one to three inches or rain.
The threat for heavy, wet snow followed by periods of heavy rain will exacerbate the threat of damage to structures through Thursday. Flooding also becomes a threat in the Cordova area.
Elsewhere, blizzard warnings are in effect for the Aleutians, the Bristol Bay region and the Kuskokwim Delta through Monday afternoon to Tuesday morning. Winds gusting to 50 mph, heavy blowing and drifting snow, and severely reduced visibilities are possible.
A blizzard watch is posted for Portage Valley, Turnagain Arm, and the Valdez area for blizzard conditions at times Monday night and Tuesday.
A high-wind warning is in effect for Turnagain Arm and the Upper Hillside of Anchorage beginning Monday night and continuing into Tuesday. Glen Alps could see gusts approach 90 mph. Gusts in town will range from 30 to 60 mph.
These strong downsloping winds will limit snow in Anchorage and the Valley Monday night and Tuesday. As the winds are accelerated through channeled terrain and descend off the mountains to sea level, a Chinook -- a drying and warming wind that can cause dramatic spikes in temperature -- becomes likely. Should a spike occur in Anchorage. areas of town may see temperatures climb for a few hours into the upper 30s and 40s from Tuesday afternoon to early Wednesday, then fall back below freezing Wednesday night.
If the Chinook does materialize, there is a threat for light rain in Anchorage Tuesday night or Wednesday. Snow may resume on the back side of the storm as it exits to our east, leading to accumulations of two to four inches through Thursday night.
This storm has the potential to bring heavy rain and snow, hurricane-force winds, blizzard conditions, and localized flooding to Alaska through midweek. Please take precautions now and make sure to follow us on Channel 2 Weather's Facebook page and at KTUU.com's Weather section for updates and forecast revisions as needed.
Contact Mitch Sego