Strong SW winds in excess of 80 mph will accompany periods of heavy snow Tuesday into Tuesday night and will load exposed NW-N-NE-E-SE facing slopes near and above treeline. Triggering these wind slabs by a rider will be likely Tuesday and Wednesday and it is recommended to remain off of any wind loaded slope steeper than 35 degrees during that time. Clues to look for include pillowy slopes just below newly formed cornices and slopes where drifting new snow is being deposited.
12-18" of dense new snow is expected through Wednesday morning which will fall on a variety of suraces, including slick sun and melt-freeze crusts that formed during last week's warm weather. Bonding will be poor between the old and new snow interface through Wednesday and it will be possible to trigger a storm slab avalanche on all sheltered slopes steeper than 35 degrees. Look for collapsing and cracking and avoid slopes where these clues are evident.
The last 2 weeks of warm spring-like weather greatly impacted the snowpack in the BWRA, with lower elevations beginning to melt out, upper elevation southerly slopes becoming nearly isothermal, and upper elevation northerly slopes still holding on to dry snow throughout the snowpack. The Leavitt Lake SNOTEL station finally reported an air temperature at the freezing mark this morning after being above freezing for 12 days. Surprisingly, due to shading and aspect, there was little melting over these 12 days as the station reported no loss of SWE. Further down at the Sonora Pass SNOTEL station, some melting has been occuring as the SWE decreased by about 2" last week. Cloud cover and winds have inhibited a lot of the surface melting this past week and over the weekend leaving sun and melt-freeze crusts on a number of slopes in the BWRA.
Observations made on Saturday in the BWRA revealed a variety of conditions including a wet springtime snowpack on lower elevation and southerly facing slopes and a mostly dry wintertime snowpack, with the exception of a thin layer of wet snow on the surface, on slopes with more of a northerly component. Stability tests showed some instability with very wet snow near the surface on southerly slopes but also showed no propensity for propagation. The rest of the snowpack was strong and quite stable.
A series of storms will impact our area through early next week, with the first storm hitting our area today. We have already picked up between 2-5" of wet heavy snow in the BWRA this morning with an additional foot expected through Wednesday morning. Luckily snow levels will be dropping through the day today and overnight leaving us with some lighter powder on top of denser snow. We'll see a brief break in snow Wednesday morning with snow showers developing in the afternoon bringing an additional 2-3" of light powder. Winds will be very strong Tuesday with gusts approaching hurricane force at the ridgetops, tapering down Tuesday night into Wednesday. Another system approaches our area during the day on Friday through Saturday morning bringing the potential of another 6-12" of snow to the BWRA.
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.
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