An active weather pattern has finally returned to Southcentral. Yesterday saw periods of heavy snow, rain showers up to 1100′ and gusty winds along ridge tops. There was also an afternoon spike in temperature bringing the warmest we have seen this spring. Snow continues to fall this morning bumping storm totals to over foot across the region and up to 2′ in Girdwood Valley, Portage and most likely Placer. Spring storms can bring somewhat complicated avalanche conditions to mountains due to the variety of issues. Today due to active loading and the chance of clearing in the afternoon with direct sunshine we recommend avoiding travel in avalanche terrain. Avalanches may run into the flats below. Avoid runout zones.
STORM/WIND SLABS: Snow surface prior to this storm consisted of surface hoar with loose faceted snow underneath on shaded aspects, and a sun crust on solar aspects (SW – SE). Both of these surfaces will be hard for the new snow to stick to. Storm related slabs are likely and are expected to be easy to initiate. Easterly ridgetop winds yesterday will have also made slabs more cohesive on leeward slopes. These could be hard to distinguish due to new snow on top.
DRY LOOSE SNOW AVALANCHES (SLUFFS): Both natural and human triggered dry loose snow avalanches on steeper terrain are likely especially on slopes with slick sun crusts and features protected from any wind.
WET LOOSE AVALANCHES: If snow turns to rain wet loose activity will be likely at low elevations. In addition, if there is afternoon clearing and the sun pokes out warming the snow surface, wet loose avalanche activity on Southerly slopes will also be likely.
Tincan yesterday. Photo: Andy Moderow
Petes South at 6:00 pm. Recent loose snow avalanches on the south face after a period of clearing.
Over the weekend there were two human triggered avalanches. On Saturday there was a snowboard triggered slide in Warm-up Bowl on a slope with previous tracks on it. On Sunday there was a small slab avalanche on a steep Northern chute on Orca, near Girdwood. These are good reminder that some slopes harboring old slabs 1-2′ thick are sitting on weak faceted snow. These slabs are composed of last week’s storm snow. There is a chance that avalanches occurring today could step down to weak layers deeper in the snowpack, another reason to avoid avalanche terrain today.
Warm-up Bowl snowboard triggered avalanche. Photo: Craig Brokensha
Yesterday was an active weather day with periods of heavy snow, rain showers below approximately 1100′, pockets of clearing, gusty SE winds and rapidly warming mid-day temperatures. Accumulations ranged from around 6″ at Turnagain Pass to over a foot in Girdwood, Portage and Placer. Temperatures spiked in the late afternoon with Center Ridge hitting 39F around 1 pm. Precipitation turned from rain to snow at lower elevations for a few hours. SE Winds were 10-20 mph and gusted into the 30s.
Overnight temperatures dropped into the 20s and snowfall picked up early this morning adding to the snow totals. Snow is expected to continue today with an additional 3-11″ forecasted. Winds will be light and easterly. Temperatures will be in the 20Fs to low 30Fs. There will be a break in systems this evening with the next storm moving in tomorrow afternoon. This next storm is forecasted to be stronger and warmer.
|Temp Avg (F)||Snow (in)||Water (in)||Snow Depth (in)|
|Center Ridge (1880′)||32||6||.4||69|
|Summit Lake (1400′)||29||7||.4||36|
|Alyeska Mid (1700′)||30||13||.9||72|
|Temp Avg (F)||Wind Dir||Wind Avg (mph)||Wind Gust (mph)|
|Seattle Ridge (2400′)||24||SE||12||30|
|04/21/21||Turnagain||Observation: Sunburst||Schauer/ Behney Forecaster|
|04/19/21||Turnagain||Avalanche: Triangle, Seattle creek||Will Morrison|
|04/18/21||Turnagain||Avalanche: Turnagain Pass Road Obs||Andy Moderow|
|04/18/21||Turnagain||Observation: Seattle Ridge, approximately 300 yards south of the up track||Brent Byrne|
|04/17/21||Turnagain||Avalanche: Road obs||Johnston-Bloom / Moderow Forecaster|
|04/16/21||Turnagain||Avalanche: Seattle Ridge||Wendy Wagner Forecaster|
|04/16/21||Turnagain||Avalanche: Turnagain Pass, non-motorized side seen from Seattle Ridge||CNFAIC Staff Forecaster|
|04/16/21||Turnagain||Observation: Sunburst||Lance breeding|
|04/15/21||Turnagain||Observation: Tincan||Schauer/ Rothman Forecaster|
|04/13/21||Turnagain||Observation: Turnagain Pass Road Obs||A Schauer Forecaster|
Status of riding areas across the Chugach NF is managed by the Glacier and Seward Ranger Districts, not avalanche center staff. Riding area information is posted as a public service to our users and updated based on snow depth and snow density to prevent resource damage at trailhead locations. Riding area questions contact: email@example.com
|Area||Status||Weather & Riding Conditions|
This is 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.