Most of the snow moving activity has involved the solar aspects & melting of surface layers. Temperatures are barely freezing at night leaving the uppermost snowpack in constant creep. Continuous periods lacking a refreeze does not bode well for our snows longevity. Reaching highs of 50F degrees during the day in February is uncommon. Although not relatively large in size a wet loose avalanche has the possibility to knock you off your intended route & into terrain that is undesirable.
Varieties of wind slab are noticeable, especially above treeline. Most are soft & unsupportable but some are firm & can hold the weight of sled & rider. The slabs that can support weight & are hollow sounding are to be avoided. These stronger slabs can likely fail catastrophically & propagate above you, entraining more snow from starting zones. Pay close attention to the aspect you intend to ride, North through East aspects have been loaded.
Let us not forget about the deeper buried weak facetted layers that linger in the snowpack. The depth of these weak layers is variable across the landscape (50 to 80cm below surface) but its availability is constant. While snowmobiling a keen observer can notice whumphing & collapsing underneath them, indicative of potential avalanching.
We are transitioning to a more spring-like snowpack with temperatures at night barely freezing. Surface layers are getting rapidly warmed & loose wet avalanches are occurring on solar aspects. Wind slab are variable with hollow pockets underneath the more supportable slabs. The snowpack is showing wind effected layers sandwiched by melt-freeze crusts, with a persistent (facetted) weak layer below 60cm (23") within treeline areas. The thin veneer of snow that exists below 8500' is melting away quickly. Percolation of melting surface snows may lubricate underlying layers & cause shear failures.
We have been snowmobiling the BWRA for two days & observations have been positive for those recreating. Slopes are holding in tact on leeward aspects that have developed soft wind slabs. Areas that are on solar aspects have shown roller-balls & wet avalanche actively, & riders are avoiding them. ESAC was submitted an avalanche observation from Virginia Lakes that is worth reading.
|0600 temperature:||31 deg. F.|
|Max. temperature in the last 24 hours:||51 deg. F.|
|Average wind direction during the last 24 hours:||Northeast|
|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:||23 inches|
Hot & annoying weather is predicted for the future week. Temps in the high 40's to low 50's is forecasted with no precipitation in sight. Thin snow coverage is being replaced with bare ground (mud) & greening vegetation. Winds will come from the West with moderate severity, & no snow is available for transport.
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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