The storm system that moved out of the area yesterday left us with quite a mix of snow, freezing rain, and rain. We received 3.5cm (1.38in) of water equivalent (QPF) over the past 48 hours. This fell in the form of 10cm (3.9in) of snow followed by ice pellets and light rain yesterday afternoon as we crept up to 3C (37F) here at Hermit Lake. Last night temperatures plumetted to the current of -4.7C (23F) at the 1160m (3800ft) level. This has frozen freewater and ice pellets together creating a crust between 1cm and 1.5cm (.4-.6in) thick on the surface. Expect thickness to vary with elevation, but above freezing temperatures extended through avalanche paths to the start zones. This is the primary factor in the reduction of the current danger rating. However now we have a cold crust that new snow will have difficulty bonding with during future precipitation events. Today's summit forecast is calling for winds from the W at 50-65kph (30-40mph) with a chance of snowshowers. Although not much is expected keep an eye out for developing pockets of new snow on existing crust particularly in the strong lee areas of W winds.

Light snow is forecasted each day this week. Currently the National Weather Service (NWS) is expecting between a 40-70% chance of light accumulations each day until next weekend. These are the exact type of conditions along with a cold crust that can bite you unexpectedly. Approach new pockets through the week with suspicion and expect them to be poorly bonded with the current surface crust until proven otherwise. Only 2.5-5cm (1-2 in) of snow with moderate SW-NW winds can load lee pockets with sizeable new slabs here on Mt. Washington. The other factor that could be interesting to watch over the next several days is the possibility of rapid facet growth beneath the crust. Temperatures are anticipated to fall to below -18C (0F) in the mountains beginning Tuesday. This will generate massive temperature gradients with an impermeable crust blocking upward vapor movement. Vapor will then likely recrystalize and may become a future weak layer particularly in areas with thinner crusts.

The John Sherburne Ski Trail is improving with every bit of snow we receive. It is still undoubtedly in early season condition and you can expect abrupt waterbars, lots of bushes and rocks hidden under new snow. A thin .5cm (.2in) crust should make it a bit more challenging so be prepared for less than ideal conditions.

Remember if the snowfield is large enough to ski or recreate on it's large enough to avalanche. As always, this advisory is one more tool to help you make your own decisions in avalanche terrain. It should be use along with your own snow stability assessments, knowledge of safe travel techniques, skill in reading mountain weather's effect on the snowpack and avalanche rescue. To improve these skills take an avalanche course. We have all the avalanche courses offered in and around the Mt. Washington Valley this winter on our website, tuckerman.org.