Snowpack Summary published on March 7, 2018 @ 10:00 am
Issued by Ryan Lewthwaite -

bottom line:

We are once again snowmobiling in the BWRA. The new snow from last week coupled with abundant sunshine has made for great riding conditions. The mountains have been going through a shed & settlement phase, & there are still avalanche problems that warrant your precautions. Look for areas that haven't avalanched & keep your awareness while near steep slopes with tracks on them, as they may still hold very large avalanche potential.

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.

Strong winds during last weeks storm have created wind slabs & density changes amidst the 100cm of new snow. Natural avalanches have been observed from these slabs on slopes as mellow as 33 degrees & in unique terrain features. Slabs have also been triggered by cornice falls & are propagating along thin areas between trees & rocks.

Avalanche Character 2: 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 of the unconsolidated new snow has lead to loose wet activity. These avalanches are occurring more frequently on southern exposures & most are originating from objects heating up the surrounding snowpack.

Snowpack Discussion

We are experiencing overall good settlement of the large snow accumulations from last week. Natural avalanches occurred mid-storm or shortly after & human influences on the snowpack since has been minimal. There are still many steep slopes that look like a blank canvas which are still a potential avalanche problem. Resist the urge to be a test dummy. Most slides are using the old snow interface as the bed-surface & no step-down Deep Slab issues have been seen. The storm has broke & fallen many large trees around Leavitt Lake, & they are now just poking through the snow. Saying all this definitely does not mean its safe out there yet. Be cautious, use good judgment & keep your partners close.

recent observations

We are able to cover more ground each day with the snows support, but getting stuck is inevitable. We haven't seen any new avalanches since the end of the storm on Saturday. Riders have been exploring terrain & getting into steeper slopes without much avalanche activity. Leavitt Cirque had a large SS-N-R3-D3 avalanche & SW of the Leavitt snotel another SS-N-R2-D2 avalanche occurred on a quiet 33 degree slope(see photos). The last pic is of myself on the large drift at the Leavitt Lake Snotel which reads 114" or 290cm. This remote weather instrument used to measure water recharge into the surrounding drainage basin, is not representatively showing snow depth. The depth shown has been largely effected by its location being surrounded by trees, mid-snowpack bridging crusts, wind transport & human interference.

CURRENT CONDITIONS Weather observations from Sonora Pass
0600 temperature: 23 deg. F.
Max. temperature in the last 24 hours: 40 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: 51 inches

Clouds & near freezing temps today & slightly warmer tomorrow. A few minor snow showers tonight & potentially a good size storm on track for Tuesday.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8000 ft. to 10000 ft.
  Wednesday Wednesday Night Thursday
Weather: Mostly cloudy Partly cloudy then clearing Partly cloudy
Temperatures: 39 - 46 deg. F. 23 - 28 deg. F. 42 - 50 deg. F.
Wind direction: Southwest Southwest Southwest
Wind speed: 10 to 15 mph; gusts to 25 mph 10 to 20 mph; gusts to 30 mph 15 to 20 mph; gusts to 45 mph
Expected snowfall: 0 in. 0 in. 0 in.
For above 10000 ft.
  Wednesday Wednesday Night Thursday
Weather: Mostly cloudy Partly cloudy Partly cloudy
Temperatures: 32 - 38 deg. F. 19 - 24 deg. F. 34 - 41 deg. F.
Wind direction: South Southwest Southwest
Wind speed: 15 to 25 mph; gusts 25 increasing to 35 mph 15 to 25 mph; gusts to 35 mph increasing 30 to 45 mph; gusts to 70 mph 30 to 45 mph; gusts to 70 mph
Expected snowfall: 0 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.