Posted 8:30a.m., Friday, February 25th, 2011
Tuckerman and Huntington Ravines will have HIGH avalanche danger. Natural avalanches are likely and human triggered avalanches are very likely. Travel in avalanche terrain is not recommended. The only exception to this rating is the Little Headwall, which has Moderate avalanche danger. Natural avalanches are unlikely and human triggered avalanches are possible.
Today brings both good and bad news. The good news is that we’re getting snow today, and the forecast is now entirely free of the sleet that was a possibility for the midday hours. It seems like it’s been a while since we’ve had a good storm, so this will freshen things up a bit around here. The bad news is that the shift in the track of the storm means we’ll be getting less snow than was forecasted in previous model runs. Currently, the National Weather Service is forecasting 4-8″ (10-20cm) across the greater Mount Washington region and 6-10″ (15-25cm) on the higher summits, while the Observatory is forecasting 8-12″ (20-30cm) for the higher summits. Both of these are down from the previous forecasts of 10-14″, which is the bad part of the news.
Regardless of exactly how much snow we get today, the outlook for avalanche danger will remain the same. Today expect increasing avalanche danger throughout the day. By the end of our forecast period we will be firmly into the realm of High avalanche danger. Winds today will quickly whip around from the SW to the SE, E, NE, N, and finally settling into a NW flow by late evening, all the while increasing in velocity. In the early part of the storm, when winds are from the SE and E, there won’t be much in the way of direct loading, but some cross loading may occur. During this time, a weak unconsolidated layer will be laid down across much of our avalanche start zones. As winds wrap around to the NE and N, we’ll begin to see more direct loading on S-facing slopes and more cross-loading on E-facing slopes. By the time winds have moved around to the NW they will be blowing around 65-80mph (105-130kph) with higher gusts, providing ample loading in all of the forecast areas of Tuckerman and Huntington Ravines, all of which will fall on the unconsolidated snow from early in the day. In all areas the avalanche danger will be on the rise, however, due to the progressive winds, slopes with S-facing aspects will be leading the pack. Examples include North and Damnation gullies in Huntington and Lobster Claw and Right Gully in Tuckerman. Other areas will follow closely behind. I know many of you like to hit the gas pedal when the traffic light turns yellow and sneak through before it turns red. If you’re thinking of hustling up here and getting through before it gets too bad, you might be lucky enough to pull it off. But just like running a red light into oncoming traffic, trying to race the storm might lead to you getting blindsided by a force greater than anyone’s body should be subjected to. The good news of that scenario is that with the fog and falling snow you wouldn’t likely see it coming. In reality, there is nothing good about being involved in an avalanche; for this reason we do not recommend travel in avalanche terrain today.
Though you won’t find us in avalanche terrain, we’ll be monitoring snowfall closely. Winds tonight are going to continue to pick up in speed, getting quite strong by daybreak. Expect a lot of blowing snow tomorrow, and consequently elevated avalanche danger. If your plans include a trip to Mt. Washington this weekend, I’d recommend looking at our Weekend Update this evening and the Avalanche Advisory in the morning, both can be found on our website www.mountwashingtonavalanchecenter.org.
- Safe travel in avalanche terrain requires training and experience. This advisory is just one tool to help you make your own decisions in avalanche terrain. You control your own risk by choosing where, when, and how you travel.
- Anticipate a changing avalanche danger when actual weather differs from the higher summits forecast. For more information contact the Forest Service Snow Rangers, the AMC at the Pinkham Notch Visitor Center, or the caretakers at Hermit Lake Shelters or the Harvard Cabin.
- This advisory expires at midnight. A new advisory will be issued tomorrow.
Jeff Lane, Snow Ranger
USDA Forest Service, White Mountain National Forest
(603) 466-2713 TTY (603) 466-2856