| Posted: 9:00 a.m., Thursday, February 7, 2008 |
Huntington Ravine has CONSIDERABLE avalanche danger today. Natural avalanches are possible and human triggered are probable. Unstable slabs are probable in avalanche terrain. Be increasingly cautious in steep terrain.
You'll likely hear us talking on and off about how well areas have been filling in with snow as we are back in the snowfall pattern we saw in December. In the past 6 days we have picked up 23.25" (59cm) of snow, 12+" (30.5cm) of which fell with this storm in the past 30 hours. We saw another large avalanche occur yesterday morning in Hillman's, as well as activity in the Lower Snowfields, and the Sluice. Sluffing occurred in all the Huntington Gullies with a fracture visible in Damnation. The second half of this storm came on the trend of falling temperatures which is likely to continue today. This will keep snow from settling and keep it primed for transport when the wind finally picks up from the light velocities of today. Winds are currently from the SE blowing at 21mph (33kph). They will eventually move to the S and are expected to stay below the current speeds. So loading will be light and likely limited to northerly aspects such as Hillman's, Left, The Escape Hatch, South, and Odell gullies. You can expect some cross loading of easterly aspects but this should be limited. Although we have multiple aspects rated at Considerable they all fall with the rating's definition. With this said the northerly aspects just discussed have more instability to worry about particularly high in start zones where new loading will be focused.
Some Bulls-eye points to remember today and some long term ideas to file away: #1. We have picked up 2 feet in the past 6 days half of which fell in the past 30 hours. This generated some natural avalanche activity yesterday which offered excellent information about instability. Allowing some consolidation/sintering time after a big snow event is usually a prudent move. #2. Wednesday's storm initially came in as light density snow, becoming heavy quickly, and then becoming light again. This has caused a mid layer of heavier snow on top of the fluffy snow beginning which landed on a thin crust from the warm temperatures we saw on Tuesday. This is likely causing our natural activity #3. Snow will linger in alpine and sub-alpine locations waiting for a wind ride into the weekend. After daylight today winds will vacillate between the SW and W over the next few days very slowly ramping up velocities. Saturday's winds should still be tempered by the mild gradient, but should move into the 30's mph. (50+kph). Saturday night's storm will bring snow and increased winds for Sunday. It could get interesting around here. And #4.- A big picture concept to keep in your mind for the rest of the season. There are certain locations particularly with northerly aspects that are doing quite well for coverage and filling in with snow. Hillman's as an example ran big twice in the past 4 days talking out brush and trees in its wake. The first of the two was the second largest avalanche I have seen in that location over the past 18 years. The take home point is many start zones are fully developed with terrain features covered and have already avalanched many times this season. These slides have filled in their run out zones with snow and cleaned out brush creating an excellent environment for future avalanches. This has occurred earlier this winter season than we have seen in a long time. You can anticipate regular avalanche cycles in these developed paths with future snowfalls for the remainder of the season.
Crampons, an ice axe and solid self arrest skills are recommended for travel in steep terrain. This includes the Lion Head Winter Route. The Sherburne Ski Trail is open with new snow and full coverage.
| Please Remember: | ||||||
|
Avalanche Advisory Archives.
United States Avalanche Danger Descriptions.
Échelle Canadienne de risque d’avalanche.
| Back to the Tuckerman Ravine Home Page |