THIS SNOWPACK SUMMARY EXPIRED ON January 25, 2015 @ 6:27 pm
Snowpack Summary published on January 23, 2015 @ 6:27 pm
Issued by Adam Babcock - Bridgeport Avalanche Center
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.

Some wind slabs on shaded aspects up high may harbor cold, dry facets underneath to which they are poorly bonded.  Be cautious of hollow-sounding windslabs on very steep/extreme terrain above 9000' on northerly aspects, especially if consequences are high (getting carried over a cliff, swept into a terrain trap/creek bottom, etc.). 

Avalanche Character 2: Normal Caution
Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features. Use normal caution when travelling in the backcountry.

Be aware of extremely slippery surfaces such as raincrust-glazed bulletproof windslabs, especially when consequences are high (slide-for-life into trees, rocks, over a cliff, etc.).

Snowpack Discussion

DESCRIPTION:  The snowpack is THIN and FIRM in most places above AND below treeline.  Bulletproof windslabs glazed with rain crust, and widely distributed melt/freeze crusts are the most prevalent surface conditions.  Many ridgetops are windswept to bare ground.  Some soft, faceted snow (recycled powder in old school terms) can be found on shaded terrain features totally protected from wind and sun.  Sunny aspects have been warming enough by mid-day to soften the surface 5cm of snow.  The snowpack has been through several melt/freeze cycles, yielding corn snow, melt/freeze crusts, and water-ice formations in the snowpack.

THE BOTTOM LINE:  Overall, snowpack stability is good.  Human-triggered avalanches are unlikely, but possible in isolated areas or extreme terrain.  With all the warm temps and melt/freeze action, the snowpack - even on northerly aspects - has gained strength.  That said, pockets of windslabs above treeline may be poorly bonded to cold, dry facets below.  Very steep/extreme terrain features (including creekbanks and ravines) on shaded, northerly aspects above 9000' may be capable of producing avalanches large enough to bury/injure a person.

recent observations

Several recent snowpits above and below treeline have revealed snow depths ranging from 38cm - 104cm, the deeper ones from windloading.   Results from recent column tests have yielded only one planar fracture on a Compression Test (CTH or CT21, Resistant Planar).  No recent avalanches, collapsing/whumpfing, shooting cracks, or propagating fractures in Extended Column Tests (ECT's) have been observed recently in the BWRA.  No wet loose avalanches have been observed from diurnal warming, only occasional roller-balls that have not even grown to pinwheel size.

weather

Warm and dry weather will persist through the weekend, with high winds forecast for Friday night through Saturday.  The extended forecast calls for some light precipitation Tuesday and Wednesday, though no significant precipitation through the end of the month.

Two-Day Mountain Weather Forecast Produced in partnership with the Reno NWS
For 8000 ft. to 10000 ft.
  Friday Friday Night Saturday
Weather: Sunny Clear Sunny
Temperatures: 37-47 deg. F. 20-30 deg. F. 32-42 deg. F.
Wind direction: N NE NE
Wind speed: 5-15mph, gusts to 25 30-40mph, gusts to 55 25-35mph, gusts to 55
Expected snowfall: 0 in. 0 in. 0 in.
For above 10000 ft.
  Friday Friday Night Saturday
Weather: Sunny Clear Sunny
Temperatures: 30-40 deg. F. 20-30 deg. F. 32-42 deg. F.
Wind direction: N NE NE
Wind speed: 20-30mph, gusts to 45 30-40mph, gusts to 55 25-35mph, gusts to 55
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.