THIS SNOWPACK SUMMARY EXPIRED ON March 7, 2018 @ 9:41 am
Snowpack Summary published on March 5, 2018 @ 9:41 am
Issued by Ryan Lewthwaite -

bottom line:

BWRA OPEN AGAIN!! Please be advised we have seen numerous natural avalanches & the likelihood of triggering a large avalanche is possible. You will need to have your rescue gear available & the skills to use it, but more importantly exercise avoidance of an avalanche burial. Please make good travel choices & communicate with your riding partners on where to not go. We are requiring permits & they may be obtained on this site for efficiency. People's gate will be the launch point until it melts out, see you there.

Avalanche Character 1: Storm Slab
Storm Slab avalanches release naturally during snow storms and can be triggered for a few days after a storm. They often release at or below the trigger point. They exist throughout the terrain. Avoid them by waiting for the storm snow to stabilize.

An average of 100cm (4') of new snow has collected in the BWRA. The storm slab that has formed is very large & not yet stable. Leavitt Cirque has avalanched in historic fashion & is to be avoided.

Avalanche Character 2: 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.

Winds with the storm were swirling but have developed wind slabs on N-NE-S aspects. Expect any slope over 35 degrees with a wind slab to be an area of avoidance. These wind slabs will be thick & easily triggered with the weight of a human & their equipment. Cornices have grown to huge sizes on leeward aspects.

Avalanche Character 3: 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.

Warming & clear skies will allow rapid melting to occur, especially in the afternoon on South facing slopes that get direct sunlight. Roller balls & loose wet sluffs will originate from objects warming, changes in slope angle, or the addition of a recreationist. Tone down the afternoon travel to areas with less consequences.

Snowpack Discussion

A Very Deep (4') new snow accumulation sits on a suspect snowpack, & is in the midst of an avalanche cycle. Be aware that it is possible to trigger a very large avalanche with the weight of a human. This avalanche potential could last for several more days & a Deep Persistent Slab may exist. Exercise caution while traveling in the backcountry & have all your rescue gear ready!

recent observations

Many large & small avalanches were observed on all aspects at, above, & below treeline. The type of avalanches we are seeing cover much of the spectrum including: Loose Dry, Storm Slab, Wind Slab, Cornice Fall, & later the Loose Wet slide makes an appearance. Observations from outside our region are expressing concern for Deep Persistent Slab problems, which should heighten your awareness. A R4D3 very large avalanche was observed in the Mt Emma area seen from Hwy 395. Below Ski Lake & Big Easy Bowl the evidence of avalanche activity was apparent. Leavitt Cirque looks to have a wrap-around crown & probably propagated a full length avalanche. We will be investigating the snowpack more today.

CURRENT CONDITIONS Weather observations from Sonora Pass
0600 temperature: 6 deg. F.
Max. temperature in the last 24 hours: 27 deg. F.
Average wind direction during the last 24 hours:
Average wind speed during the last 24 hours: mph
Maximum wind gust in the last 24 hours: mph
New snowfall in the last 24 hours: 0 inches
Total snow depth: 58 inches
weather

Sunny, dry & warming up this week. Winds will be light & clear skies will rapidly melt & sublimate snow. Weak systems are in store for later in the week with another upcoming storm possible.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8000 ft. to 10000 ft.
  Monday Monday Night Tuesday
Weather: Sunny Clear Partly cloudy
Temperatures: 30 - 36 deg. F. 9 - 14 deg. F. 37 - 43 deg. F.
Wind direction: Light winds Light winds Light winds
Wind speed: Light winds Light winds Light winds
Expected snowfall: 0 in. 0 in. 0 in.
For above 10000 ft.
  Monday Monday Night Tuesday
Weather: Sunny Clear Partly cloudy
Temperatures: 23 - 29 deg. F. 7 - 12 deg. F. 30 - 36 deg. F.
Wind direction: Southwest Light winds Light winds
Wind speed: 10 to 15 mph then light Light winds Light winds
Expected snowfall: 0 in. 0 in. 0 in.
Disclaimer

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.