|Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
|Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully; identify features of concern.
|Dangerous avalanche conditions. Careful snowpack evaluation, cautious route-finding, and conservative decision-making essential.
|Very dangerous avalanche conditions. Travel in avalanche terrain not recommended.
|Extraordinarily dangerous avalanche conditions. Avoid all avalanche terrain.
|Likelihood of Avalanches
|Natural and human-triggered avalanches unlikely.
|Natural avalanches unlikely; human-triggered avalanches possible.
|Natural avalanches possible; human-triggered avalanches likely.
|Natural avalanches likely; human-triggered avalanches very likely.
|Natural and human-triggered avalanches certain.
|Avalanche Size and Distribution
|Small avalanches in isolated areas or extreme terrain.
|Small avalanches in specific areas; or large avalanches in isolated areas.
|Small avalanches in many areas; or large avalanches in specific areas; or very large avalanches in isolated areas.
|Large avalanches in many areas; or very large avalanches in specific areas.
|Very large avalanches in many areas.
A quick moving storm is impacting Southcentral currently. We have seen light snowfall overnight with an additional 1-3″ expected today. The big news is however, the WIND… Westerly winds are slated to ramp up into the 30-45mph range with stronger gusts along the ridgelines.
Snowfall Totals so far:
Girdwood Valley: 3-5″
Turnagain Pass: 2-3″
Summit Lake: 3-4″
WIND SLAB AVALANCHES:
With plenty of older loose snow available for transport and a few new inches, fresh wind slab avalanches should be expected. These could release naturally, or be easily triggered by a person. They could be anywhere from a shallow 6″ slab to a thicker, more concerning, 18″ slab. This flow direction is known to load Easterly slopes on Seattle Ridge, such as Repeat Offender. On the East side of Turnagain Pass, this flow often loads Northerly slopes on ridgelines such as Tincan, Sunburst and Magnum.
*Keep in mind that newly wind loaded slopes could overload buried weak layers and a wind slab avalanche could ‘step-down’, triggering a larger slab avalanche.
We are glad to report a positive outcome to a near miss avalanche yesterday on the Lipps ridge. Three skiers were caught and carried in a slab avalanche while they were ascending the common up-track on the lower portion of Lipps. The avalanche was triggered in a thin area and propagated above them. The slab washed over all three and they were carried 1-200′ (estimate) before they all ended up on the surface of the debris. Forecasters will investigate this avalanche today and a more detailed report, with the events shared by the party members along with avalanche details, will be finalized soon. You can see more photos in the preliminary report HERE.
PERSISTENT SLAB AVALANCHES:
The Lipps slide was believed to be a persistent slab that broke in weak faceted snow 1-2′ below the surface. This set up exists South of Turnagain Pass (including Johnson Pass and Lynx drainages). There is a variety of weak layers that sit 1-3′ below the surface and triggering a slab breaking in the old snow remains possible. Pay attention to:
Photo from the Lipps avalanche yesterday taken by a member of the group involved. We thank these folks for their willingness to share.
Mostly overcast skies covered the region yesterday. Ridgetop winds were light from the North and East and no precipitation fell. Temperatures rose dramatically from single digits at 7am to 20F by 7pm (in response to a warm air mass moving through from the West).
Overnight, we have seen light snowfall in Girdwood, Turnagain Pass and Summit Lake as a warm storm system impacts Southcentral. This system looks to be favoring the Girdwood and Western Kenai Mountains, including Summit Lake, snowfall totals mentioned above and in chart below. Another 1-3″ of snowfall is forecast for today before skies begin to break up. STRONG Westerly ridgetop winds (30-45mph) are expected during today bringing cold air – it should be chilly and blizzard like on the ridgelines!
Tomorrow, the cold single digit air mass will remain over us with clear skies and no precipitation expected.
|Temp Avg (F)
|Snow Depth (in)
|Center Ridge (1880′)
|Summit Lake (1400′)
|Alyeska Mid (1700′)
|Temp Avg (F)
|Wind Avg (mph)
|Wind Gust (mph)
|Seattle Ridge (2400′)
|Observation: Kickstep NE Bowl
|Observation: TinCan Backdoor/ Center Ridge
|AAS L1 Turnagain
|Avalanche: Lynx Creek
|Observation: Turnagain, Seattle, Mt Ascension
|Silverton Mountain Guides
|Observation: Tincan Trees
|Dalpes/Thamm/ Schauer Forecaster
|Observation: Seward Highway across from Johnson Pass TH
|Avalanche: Base of Seattle Ridge
|Troy Tempel, Thomas Lees, .Josh Bollaert, Damian Naquin
|Observation: Lynx creek