Huntington Ravine has Low, Moderate and Considerable avalanche danger today. Central Gully has Considerable avalanche danger. Natural avalanches are possible and human triggered avalanches are probable. Unstable slabs are probable in steep terrain. Be increasingly cautious in steeper terrain. South, O'Dell's, Pinnacle, and Yale gullies have Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible. Unstable slabs are possible in steep terrain. Use caution in steeper terrain. Damnation and North currently have Low avalanche danger. Natural avalanches are very unlikely and human triggered avalanches are unlikely except in isolated pockets. Normal caution is advised.

Yesterday started off with a bang as perfect stellar snow crystals fell from the sky with light winds. This added up to approximately 2.5" (6.4cm) by late morning. As we discussed in Wednesday's advisory be ready for more snow than forecasted and if this occurs plan on the ratings to be on the upper end of their definition "nudging to the next". As winds picked up through the day it moved the 5" (12.5cm) available on the ground into eastern facing aspects in both Ravines. A fracture line near the horizon above the Tuckerman Headwall is the most prominent evidence of natural activity. Another fracture under the ice near the Lip is almost completely covered due to reloading after the event. Cold air has kept slab consolidation to a minimum so expect new slabs from yesterday to retain their elastic energy and propensity for propagation. The northern or right side of Tuckerman still possesses the most instability. The greater Lip area over to the Sluice will remain at Considerable avalanche danger today. We are most concerned about the human trigger potential being "probable" compared to the natural activity definition of the rating. As you move across the Ravine towards Left Gully the danger drops to Moderate which still means human triggered avalanches are possible. In Huntington the main unstable slabs of concern are in Central gully followed by O'Dells and then Pinnacle. There are instabilities to watch through out all the gullies in Huntington, but most have instability issues near the exits of each climb. Lower than average winds have the knack of loading lee areas with out scouring the same locations clean as our higher winds often do. When avalanche danger is either Low or High it is usually obvious as to why, but when the instability points to Moderate and Considerable it becomes more difficult to make the best decisions. This why most avalanche accidents and fatalities worldwide occur under these two ratings. Keep all your avalanches senses on today and make smart choices. The mountains will always be here tomorrow, make sure you are too.

Colder air is on the way tonight and into tomorrow. Summits will fall to between -25 and -30F (-32 to -35C) tonight and may warm up to -20F (-29C) tomorrow. Saturday will "warm" some more, but the higher elevations will still be deep into the negatives! These are brutal temperatures to the skin and body so if you venture out be sure you have the best arctic mountaineering clothing and equipment to deal with this hazard.

The Lion Head Summer Trail is still open. The Summer Trail crosses an avalanche prone slope that is still fully developing. As is smart in avalanche terrain across this and all other such slopes one at a time. The Winter Route is not built for travel without adequate snow cover.