A new snow accumulation of 7-9" fell overnight with warm temperatures & strong winds. Nearly 2" of water equivalent was recorded, meaning the new snow is wetter & less consolidated than what it sits on. The snowpack that exists is highly variable from one location to the next, or it may be bare. Sun will make this snow unstable on slopes steeper than 35 degrees.
You can't have 50 mph winds without the formation of wind slabs. Winds from the south & west have loaded slopes in contrast from the Northwest through Southeast aspects. Cross-loading of gullies & cornice creation will be apparent out there today as wind driven snow moves around the landscape. Triggering a wind or persistent slab can be possible from much lower on the slope than you anticipate.
The snowpack has had trouble maintaining a good routine this season. Fluctuations & above normal temps, prolonged dry periods, & high winds have created a structure that is poor & new loading could prove this. Facet/ crust combos are lingering within the spatially variable snowpack & likely will help propagate avalanches at these layers. Although not reactive everywhere, deeper pockets of instability exist, therefore avoiding avalanche terrain is a safer bet.
A lot is going on in a relatively small amount of snow. We are finding the base of our pack is pretty glued into place but above that is layering crusts with faceting snow grains in the mix. Tests have shown a consistent failure at 88cm (35") from the bottom up, with moderate influence. Last evening & todays new snow will be concerning as it has come in warm & wet & sits upon a poor structure.
Wednesday night pushed out 1.5" of snow in places but winds have cast it around. Overnight new snow fell above 7500' in some amounts as deep as 9" can be found. Wet & unconsolidated avalanches can be seen on steeper slopes. Blowing snow & deposition is occurring especially above treeline.
Snow has returned to the Central Sierra Mountains! Stations in the BWRA report 7-9" of new snow accumulated with temperatures near or above freezing. The moisture will continue throughout today & will be ending this evening as skies clear. Tomorrow we can see sunshine until the next band of precipitation moves in. Winds today will be strong out of the Southwest trending West with 30 to 50 mph & gusts near 80 mph! Winds shall die-off this evening & again ramp-up as the next system enters our zone. Temperatures are still unseasonably warm & rain has accompanied the snow in elevations from 8500' & below.
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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