| Posted: 7:53 a.m., Friday, December 7, 2007 |
Huntington Ravine has MODERATE and LOW avalanche danger today. South, Odell, Pinnacle, Central, and Yale have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Use caution in steeper terrain. The Escape Hatch, Damnation, and North gullies have Low avalanche danger. Natural avalanches are very unlikely and human triggered avalanches are unlikely except in isolated pockets. Normal caution is advised.
Winds were expected to decrease yesterday afternoon but contrary to all forecasted wind velocities the summit gusted from the west to 91mph (145kph) late in the day. From 9am to 7pm winds gusted above 70mph (113kph) pushing towards 80mph (129kph) for several hours. It was a great example of how sometimes natures decides what it wants to do even when we think we can predict her every move. These high winds moved snow into the Ravines through the day pushing the avalanche danger ratings to their full definitions. This new loading and today's forecasted snow showers in the afternoon are the rationale for a bump in some ratings. Lee areas of WNW winds in Tuckerman loaded with the most new snow, hence the move to "Considerable" for these areas. In Huntington the focused areas of concern are Odell, Pinnacle, and Central gullies. Expect these gullies to have variable conditions, with each having some areas on the upper end of the Moderate rating. The definition of Moderate states that human triggered avalanches are possible, so in these areas careful route finding is critical. Other gullies in Huntington also carry the Moderate rating today and although they didn't receive the new snow deposition of the aforementioned gullies in the direct lee, they do hold instabilities to watch out for.
In either Ravine, a snowpack concern to remember is newer slabs have loaded over lighter density slab and unconsolidated loose snow in many areas. This creates weakness at the interface between the two layers as the lighter density snow struggles to keep the heavier snow above in place. This scenario is what we have been referring to as "touchy" over the past several days.
Early season conditions produce tremendous variability in snow stability. It's critical that you keep a focus on these differences as you travel through the terrain. You may find hard stable snow for the first half of your climb and then what appears to be out of no where you're in 24" (60cm) of slab. Constantly re-evaluate snow stability and your route. With how the Ravines have shaped up over the past few days since the storm this will be a real concern this weekend. Pay attention to the pockety nature of the mountain's instabilities. Remember that it isn't the size of the avalanche that counts, it's the consequences.
Go to tuckerman.org tonight for the season's first Friday posting of the 'Weekend Update'. Jeff will fill us in with any updates concerning today's field observations and how weekend weather may affect the Ravines. Remember, snow stability assessment and avalanche rescue skill are perishable. You must practice, PRactice, PRACTice, PRACTICE!!! Your life, and those in your group, depends on it! If buried, your life is in the hands of your partner, make them hone their rescue skill. We have all the avalanche courses offered in the valley this winter on our website.
| Please Remember: | ||||||
|
Avalanche Advisory Archives.
United States Avalanche Danger Descriptions.
Échelle Canadienne de risque d’avalanche.
| Back to the Tuckerman Ravine Home Page |