Good morning. This is Kevin Wright with the Chugach National Forest Avalanche Information Center on Saturday, December 3rd 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).
Today’s avalanche danger rating is rising towards CONSIDERABLE with a storm expected to ramp up early this afternoon. This storm brings all the ingredients needed to increase the avalanche danger – snow, rain, wind, and rising temperatures. Conditions may start out calm this morning, but expect the weather to get worse through the day.
Primary concern today is storm snow avalanches caused by intense precipitation this afternoon. The National Weather Service is confident that a strong storm will enter the region today, bringing rain, snow, and wind. This will add additional weight to the snowpack. Additional weight adds stress, and stress on the snowpack is ultimately what causes avalanches. Wind is already becoming an issue at ridgetops in Turnagain Pass and snowfall has started in Girdwood early this morning.
We expect natural avalanches to be possible, and human triggered avalanches to be likely this afternoon. Traveling in avalanche terrain today will require expert level skills to stay in safe areas.
Yesterday we got this report of naturally occurring avalanches in the Girdwood valley. This is a huge red flag! The snowfall yesterday came in stronger than expected and produced these avalanches and considerable avalanche danger in the backcountry. Any additional precipitation will increase the hazard further.
Our underlying snowpack is a secondary concern to the storm today. If you are interested, check out our most recent pit data here. We are seeing a couple of layers of concern with weak faceted snow formed during the cold snap as a potential problem. Given enough additional storm loading, it may be possible for avalanches to step down into these deeper layers. The storm snow by itself is the primary concern today, but given enough additional stress these deeper layers could turn the avalanche cycle into a much more dangerous issue. Stay tuned and keep a close eye on the snow if you get in the backcountry today.
The Seward District has opened all motorized areas. Check the riding areas at the bottom of this page for the latest updates. Placer river and Twentymile remain closed until we get more snow cover.
A tropical moisture feed extending from Hawaii will bring abundant moisture to the area through Sunday. Rain at lower elevations and heavy snow in the mountains is predicted today. The elevation of the rain/snow line could be up to 2000 feet. Snowfall amounts today and tonight is expected to be 1-2 feet. Wind will be strong through the region with a Southeast flow up to 55mph in the afternoon. Hold onto your hat!
Wendy will issue the next advisory tomorrow morning. 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.