Snowpack Summary published on March 18, 2021 @ 8:04 am
Issued by Joseph Soccio - Lead Snow Ranger

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Heightened avalanche conditions exist today on specfific terrrain features. It is possible to trigger small loose wet avalanches on lower elevation slopes today. Terrain below tree line may receive rain this afternoon. Avoid slopes that show signs of loose wet instability this includes mushy wet snow surfaces, rapidly rising temperatures and roller balls.


Avalanche Character 1: Loose Wet
Loose Wet avalanches occur when water is running through the snowpack, and release at or below the trigger point. Avoid very steep slopes and terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.

Small loose wet avalanches are possible today at lower elevations. Snow that is forecasted at higher elevations may fall as rain in locations below 8,000 ft. Limited amounts of snow are forecasted for today but if the precipitation falls in the form of rain rather than snow, your travel plans should reflect avoidance of slopes receiving rain. The slick surface conditions at higher elevations have created an ideal situation for long sliding falls if you were to lose an edge. Remember to be also be mindful of terrain traps that may be below you.

Snowpack Discussion

As the calendar moves into mid March our snowpack and weather are following suite for this time of year. A mixed bag of weather events has provided a checkerboard of variable surface conditions. Today, on the verge of another storm, there is uncertainty regarding the elevation where the rain/ snow line will occur. The current timing of the storm shows a significant increase in snowfall rates after sunset . As we anticipate the incoming storm and wintery conditions, remember the avalanche hazard will change quickly overnight, just like our current weather pattern.

CURRENT CONDITIONS Weather observations from Sonora Pass
0600 temperature: 21 deg. F.
Max. temperature in the last 24 hours: 44 deg. F.
Average wind direction during the last 24 hours: SW
Average wind speed during the last 24 hours: 30 mph
Maximum wind gust in the last 24 hours: 42 mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 48 inches

A cold, late season storm brings rain, snow and gusty winds to our region today and Friday. Expect moderate southwest winds today. Forecasted snowfall amounts range from 9-18” by Saturday morning. Daytime highs will be the upper 30’s. Heavy snow is forecasted to fall tonight but don’t be surprised if much lighter amounts fall.  

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8000 ft. to 10000 ft.
  Thursday Thursday Night Friday
Weather: Partly cloudy. Slight chance of snow in the afternoon. Mostly cloudy. Chance of snow in the evening, then snow after midnight. Mostly cloudy. Snow.
Temperatures: 36 to 46. deg. F. 25 to 30. deg. F. 33 to 43. deg. F.
Wind direction: South South South West
Wind speed: 15 to 20 mph. Gusts up to 35 mph increasing to 45 mph in the afternoon. 15 to 25 mph with gusts to 50 mph. 15 to 25 mph with gusts to 50 mph.
Expected snowfall: 1 inch. in. 70% probability of 3 to 7 inches. in. 70% probability of 2 to 6 inches. in.
For above 10000 ft.
  Thursday Thursday Night Friday
Weather: Partly cloudy. Slight chance of snow in the afternoon. Mostly cloudy. Snow. Mostly cloudy. Snow.
Temperatures: 27 to 35. deg. F. 19 to 24. deg. F. 25 to 33. deg. F.
Wind direction: Southwest Southwest Southwest
Wind speed: 15 to 30 mph. Gusts up to 45 mph increasing to 60 mph in the afternoon. 25 to 40 mph with gusts to 65 mph. 30 to 45 mph with gusts to 70 mph.
Expected snowfall: 60% probability up to 1 inch. in. 80% probability of 2 to 7 inches. in. 90% probability of 2 to 6 inches. 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.