Tuckerman and Huntington Ravines have HIGH avalanche danger. Natural and human triggered avalanches are likely on a variety of aspects and angles. Unstable slabs are likely and travel in avalanche terrain is not recommended. As is typical during early season the variability of surface conditions and stability is great. Undoubtedly new snowfields have grown but are yet unseen due to whiteout conditions. So today's HIGH posting will have instabilities true to the definition. But these conditions aren't as widespread as a mid-winterstorm of 27.5 inches (70cm) when all snowfields are already established. There are numerous locations such as the top of Hillman's Highway that have unstable conditions, but have very limited paths established so avalanche activity will have short runs. Other areas like Left gully are just the opposite where full snow run-outs are already established. This means avalanches may run their full "mid-winter" distances. This is also the case in Huntington were I would expect large avalanches to be likely in the northern gullies (Yale, Damnation and North) and less likely in South gully. Therefore the spatial variability will be great and expect natural avalanche activity in numerous locations in both Ravines to fill the entire spectrum relative to their paths (I.e. large and small). These early winter conditions also warrant using the 5 scale system for some locations and not for others. So we are not posting a rating for the Lower Snowfields and the Little Headwall in Tuckerman and the Escape Hatch of Huntington until needed. It is also possible that we may go back to a "General Advisory" if we return to normal mid-autumn weather. While in 5 scale we will issue a new Advisory daily while a General Advisory will be updated as needed. So check back daily.

The 27.5 inches (70cm) of new snow on the summit fell over the past 30 hours and came in with a high moisture content melting down to 4.43 inches (11.25cm). This creates a high density average of 16% snow. As this slow moving Nor'easter moves up into the Maritimes today wrap around moisture will continue the winter storm warning for the mountains. Snow is expected to continue and turn upslope later and become more sporadic. Several more inches should be expected. Eventually later today winds will shift from the current NNE to the NW. When the shift begins it should proceed fairly rapidly as the nearby Low moves off to the NE. The GFS model has been fairly true and predicts this shift to occur early this afternoon around 1pm. The wind velocity which subsided overnight and have begun to pick up again. They are anticipated to be pushing 75mph (120kph) late in the day and should make things very interesting. Although winds topped out at over 100mph (160kph) from the ENE late last night there is an enormous amount of snow left above treeline that will load directly into the easterly aspects of both Ravines. Anticipate loading of southern aspects through the first half of the day with NE to N winds and then the larger easterly facing slopes loading when the winds move from the NW.

ICEFALL- With colder temperatures on the way be aware of falling ice when we get into freeze thaw periods before the real deep winter freeze. Many folks have been injured and killed by falling ice so pay attention to where you are, and don't linger when under ice. Have a plan in mind about what you will do and where you will go if ice comes down. Station yourself near a large rock to duck behind in the event of ice fall.

GENERAL TRAVEL- The high mountains are absolutely in full winter conditions so don't plan on being able to follow summer trails safely. Trails going through ravines and gulfs are buried with snow in many areas and require winter gear, i.e. winter clothes, ice axe, crampons, avalanche beacons, shovels, and probes. Don't wait any longer to refresh your avalanche skills. Pull out your beacon and practice. Review your safe travel rules, techniques for assessing snow stability, and sign up for an avalanche course. We will have all the avalanche courses offered in the valley this winter on our website, tuckerman.org very soon.