Quick report
Very cold and very windy conditions combined with very poor visibility limited my ability to assess the effects and outcomes of wind loading in avalanche terrain today. There are some key observations made that support the accuracy of the current General Avalanche Bulletin.
- Light but steady snowfall occured throughout the day above 3500 feet at a rate of less than 1cm per hour. This snow was very light density and was easily being picked up and moved (maybe to Maine) by 60 - 75 mph summit wind speeds.
- Snow surfaces are variable. I traveled on old ice crusts and rock in very exposed locations, stiff, compacted 'wind board' in lee locations, and softer (yet still wind affected snow about 10-15cm deep) in wind-sheltered locations.
- The observed snowpack was generally stable, though I would be questioning the size and sensitivity of new wind slabs in the most wind protected areas such as on steep southeast-facing slopes and protected terrain pockets, below cliffs, and in very narrow couloirs.
Weather
- Air Temp
- 1
- Cloud Cover
- obscured
- Wind Loading
- moderate
- Recent Snowfall
- 2
- Snow Avail For Transport
- small smounts
The immediate Mount Washington area was in the clouds with significant blowing snow, leading to very poor visibility. Northwest winds were very strong and gusty around the Hermit Lake area and temperatures were in the single digits F. Light snow showers were consistent throughout the day, and mostly occuring above 3500 feet in elevation at an estimated rate of <S1.
Snowpack
Snowpack depths are still shallow for this time of year. Depths below 4200 feet were variable from 35 - 80cm, seemingly based on a particular slope's exposure to the wind.
A sandwich of old ice crusts below variable depths of wind-hardened snow seems to be widespread across middle and upper elevation terrain. In the most exposed areas, the snowpack surface is scoured down to the 1-week old ice crust. In the most sheltered areas, the snow surface was 10 - 15cm of softer, wind-affected snow. Though I found poor structure when digging through multiple crust layers with faceted grains in between, the bridging ability of these crusts was strong and overall, the snowpack seems generally stable.