Snowpack Summary published on March 6, 2021 @ 8:20 am
Issued by Jason Mozol - Bridgeport Avalanche Center

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Last night, southwest winds gusted over 100mph with up to 2” of new snow forming small wind slabs on NW-SE aspects. Human triggered avalanches will be possible. 

Avalanche Character 1: Wind Slab
Wind Slab avalanches release naturally during wind events and can be triggered for up to a week after a wind event. They form in lee and cross-loaded terrain features. Avoid them by sticking to wind sheltered or wind scoured areas.

Gale force winds blew from the SW last night and continue to gust over 100mph this morning. These winds combined with uncertain amounts of light snowfall and movement of older snow have created wind slabs on NW-SE aspects. Winds of this magnitude form slabs in unusual, unpredictable locations, outside the typical alpine zones, over cross ridges and further down drainages. Take note of any cracking, whoomphing or smooth pillow looking features in the snow. Below these slabs are variable crust surfaces, or facets on protected northerly aspects, and will take more than a single day to bond. 

Snowpack Discussion

Given the uncertainty of how much new snow fell last night, it will be important to take note of how much, if any, fell in the location you are in. Areas with more snow will have larger wind slabs, be more susceptible to warming and require more careful travel. Smooth crust layers exist under the new snow and increase hazards of travelling in the backcountry. Take note of what hazards such as rocks, cliffs and trees are below you. 


Sunday brings a return to calm, warm weather and a greater likelihood of small wet loose avalanches. The new snow layer will be most affected by warming conditions, creating wet snow instabilities. The wind slabs that formed last night will persist, necessitating continued assessment. Moving into next week, strong winds return with more opportunities for snowfall.  

CURRENT CONDITIONS Weather observations from Sonora Pass
0600 temperature: 29 deg. F.
Max. temperature in the last 24 hours: 47 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 16-60 mph
Maximum wind gust in the last 24 hours: 111 mph
New snowfall in the last 24 hours: 0-2" inches
Total snow depth: 87 inches

A fast moving storm moves out of the region this moring giving way to clearing skies and moderate temperatures. Winds will likley remain strong throughout the day. 

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8000 ft. to 10000 ft.
  Saturday Saturday Night Sunday
Weather: Partly cloudy becoming sunny Clear Partly cloudy
Temperatures: 34 to 44 deg. F. 21-27 deg. F. 37-47 deg. F.
Wind direction: SW SW SW
Wind speed: 25-35mph, gusting to 90mph 15-20mph, gusting to 40mph 15-20mph, gusting to 40mph
Expected snowfall: 0-1 in. 0 in. 0 in.
For above 10000 ft.
  Saturday Saturday Night Sunday
Weather: Mostly cloudy then becoming sunny Clear Partly cloudy
Temperatures: 27-35 deg. F. 16-21 deg. F. 30-38 deg. F.
Wind direction: SW SW SW
Wind speed: 50-70mph with gusts to 115mph 15-30mph with gusts to 50mph 15-30mph with gusts to 45mph
Expected snowfall: 0-1 in. 0 in. 0 in.

This snowpack summary applies only to backcountry areas in the Bridgeport Winter Recreation Area. Click here for a map of the area. This snowpack summary describes general avalanche conditions and local variations always occur. This snowpack summary expires in 48 hours unless otherwise noted. The information in this snowpack summary is provided by the USDA Forest Service who is solely responsible for its content.