|Travel Advice||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.|
Man, what a warm day yesterday. For any folks that were out and about there was a marked change in temperature – and snow quality – in the afternoon. Temperature at 1,900’ (Center Ridge SNOTEL) went from 36F to 39F between noon and 1pm which turned the soft “cream cheese” powder to sticky and difficult riding. There were several wet loose avalanches over the course of the day on all aspects below 3,000’. These were both natural and human triggered but most in the small category and confined to the upper 4-8” of damp loose snow. A few larger wet point releases were seen on the east face of Pyramid. Additionally, small wet slab avalanches were reported on the northern side of the Pass.
Today the warm and rainy conditons continue. We should see a decline in the natural wet activity but human triggered wet loose and possibly wet slab avalanches can be expected on the steeper slopes. These should be fairly small but do have the potential to become larger and more worrisome in bigger terrain where significant amounts of snow can be entrained.
Above 3,000’ in the upper alpine, where snow is falling and the wind is blowing, wind slab avalanches will be the primary concern. The moderate to strong easterly winds began to load slopes yesterday afternoon. Shallow 3-6” wind slabs were building easily but were only moderately touchy. These slabs should be thicker today and fairly stiff and stubborn to trigger. However, this is the case where they can lure you onto them before releasing, taking you for a ride. Watching for loaded slopes, cracking in stiff and hollow feeling snow and collapsing will be ways to avoid these wind slabs.
Once again, we are concerned about the deep slab avalanche problem caused by weak early season snow residing in the bottom of the snowpack. The current warm temperatures are adding to this concern today as they can act to loosen the pack as a whole. What this does in a nutshell is increase the deformation in the 3-8′ thick slab which subsequently adds stress to the weak layer below. The good news is the weak layer is becoming deeper and deeper by the day and our pit results continue to show signs that this type of large, destructive avalanche is getting harder and harder to trigger. But nonetheless, we still have to keep this problem in mind.
Warm weather continues over the Eastern Turnagain Arm this morning. Temperatures reached a seasonal high yesterday with 32F up to 3,500′ and 40F at 1,000′ €“ downright balmy. Over the past 24 hours we have only had a few tenths of an inch of rain below 1,500′ and a couple inches of snow at the highest elevations. Winds have been moderate to strong from the east €“ averaging 20mph with gusts to over 50mph.
Today warm and wet conditions remain. Ridgetop temperatures should hover around 32F, or just below, and the upper 30’s at 1,000′. A quarter of an inch of rain is expected below 2,000′ and 2-4 € of wet snow above. Expect winds to be around 25mph with gusts to 50mph.
Slightly colder air begins to move in tomorrow. A weak southeast flow should keep cloudy skies and snow flurries (with little accumulation) over us for the next couple of days.
Kevin will issue our next advisory tomorrow morning, January 23rd.
|11/27/23||Turnagain||Avalanche: Tincan Ridge||Schauer/ Stiassny Forecaster|
|11/26/23||Turnagain||Observation: Road report: Slide with dirt on Repeat offender||Anonymous|
|11/26/23||Turnagain||Observation: Pete’s North||Ben Sullender|
|11/25/23||Turnagain||Observation: Tincan trees||John Sykes Forecaster|
|11/21/23||Observation: Spokane Creek||John Sykes Forecaster|
|11/19/23||Turnagain||Observation: Magnum – PMS Bowl||Schauer/ Cullen/ Jonas Forecaster|
|11/19/23||Other Regions||Observation: Sunnyside/Penguin||Jose Ramos-Leon|
|11/19/23||Turnagain||Observation: Eddies||Andy Moderow|