Good morning. This is Kevin Wright with the Chugach National Forest Avalanche Information Center on Wednesday, November 30th at 7am. This will serve as a general backcountry avalanche advisory issued for Turnagain Arm with Turnagain Pass as the core advisory area (this advisory does not apply to highways, railroads, or operating ski areas).
There will not be an advisory issued tomorrow. Our next advisory will be issued Friday, December 2nd, at 7am.
The avalanche danger has increased overnight. Expect to find pockets of CONSIDERABLE avalanche hazard where new snow and strong wind have built windslabs that are likely to be triggered by people today. There were 3 changes that make this storm different than anything we’ve had in the last 3 weeks – storm intensity, high wind with the snowfall, and dramatically increasing temperatures. Even before this snowfall we were finding potentially dangerous windslabs. All these problems have become worse overnight.
Today’s avalanche discussion is mostly about the weather. We got variable snow amounts, from 2-10 inches through the region. The strongest pulse came in late last night, with a short intense period around 10pm. Wind also spiked around the same time with ridge-top gusts reaching up to 72mph. Wind direction was generally East to Southeast, blowing snow onto the West and Northwest slopes. Temperatures increased significantly but stayed cold enough during the snowfall to remain snow. The most dramatic increase was around Portage where the temperature rose 40 degrees in 8 hours (total increase in 24 hours was 48 degrees!).
Increased snow, wind, and temperature all produce higher avalanche danger. Also remember that we had some avalanche issues before this storm, which compounds the issue. The new snow is being added to a discontinuous windslab that formed on Sunday. This sits on top of relatively weak faceted snow from the cold snap.
Backcountry travel is possible today, but requires well tuned routefinding skills to stay in safe areas. This is a good day to avoid upper elevation areas, especially on the North and West sides of the mountains.
Snowfall is expected to continue lightly over the next several days. It looks like the bulk of this storm just skimmed us before trending farther East into Prince William Sound. The general flow pattern will remain similar for the foreseeable future, with warmer temperatures and precipitation possible every day through the week. Wind will be moderate along with the snowfall.
CNFAIC Weather Page and the NWS forecast
I will issue the next advisory Friday morning at 7am. If you get out in the backcountry we want to know what you are seeing. Please send us your observations using the button at the top of this page or give us a call at 754-2369. Thanks and have a great day.