Good morning. This is Wendy Wagner with the Chugach National Forest Avalanche Information Center on Thursday, February 2nd 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).
Alaska DOT crews will be conducting avalanche hazard reduction along the Seward Highway today. Expect intermittent road closures between 10am and 3pm. Visit http: http://511.alaska.gov/ for updated information.
Pockets of HIGH avalanche danger remain in areas where strong winds and continued snowfall and/or rain persist in the wake of yesterday’s intense storm. In most areas this morning, winds and snowfall rates are tapering off and the danger is CONSIDERABLE. Though the storm, and avalanche danger, is decreasing, dangerous avalanche conditions still exist. Human triggered avalanches are likely on ALL SLOPES at ALL ELEVATIONS today and expert level route finding skills are required for safe backcountry travel.
Heavy snowfall, rain and hurricane force winds pounded our region yesterday. The avalanche danger was updated to HIGH as the storm intensified mid-day. Natural avalanches occurred and, though driving conditions and visibility were very poor, debris piles were seen at the bottom of some avalanche paths. One of three paths at mile 106 on the Seward Highway slide and deposited snow on the road.
Storm snow instabilities are the primary concern today with continued moderate snowfall and strong ridgetop winds. These will be in the form of: Wind slabs, soft slabs and loose snow avalanches. Soft slabs were exceedingly touchy yesterday on slopes over 35 degrees in the relatively ‘safe’ treed locations. We were able to trigger these 10-16″ slabs at will on steep rollovers. This is indicative of how the snow is reacting and bonding to the old surface. Though this weakness has likely settled out to some degree today, new snow and continued wind will keep the hazard up.
Lower elevation slopes (below 1000′):
Wet avalanches are also a concern where rain has fallen on snow. Very heavy and wet snow exists at these elevations and, until cooler temperatures lock it in place, wet avalanches will be possible.
Safer places to recreate are in the flats, or on slopes less than 35 degrees, that are NOT below or connected to steeper slopes and avalanche paths.
Heavy snow and rain fell in force yesterday. Some areas saw over 3″ of snow per hour at times.
Totals from the mid elevations:
Turnagain Pass: 24-30″ snow, ~2″ water
Girdwood Valley: 28-36″ snow, 2.5-3″ water
Summit Late: 14″ snow, ~1″ water
Winds were off the charts as well. Not only did Sunburst’s wind sensor make it through 5 hours of over 100mph gusts intact, it recorded its new record gust – 126mph. Winds were southeast, sustained between 50-85mph. Needless to say, it was bona fide storm day.
Today, remnants of the storm still hang over us and we can expect moderate snowfall (around 6-10″ accumulating today) and moderate to strong ridgetop wind (southeast 30mph with 55mph gusts). The snow/rain line is currently right around sea level where temperatures are in the mid 30’s. Temperatures will be in the upper to mid 20’s F above 1000′ and should cool off tonight and into tomorrow.
CNFAIC Weather Page and the NWS forecast
Kevin will issue the next advisory Friday 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.