DANGEROUS AVALANCHE CONDITIONS
A CONSIDERABLE avalanche danger this morning will likely reach HIGH sometime today on steep, wind drifted slopes above treeline that face NW-N-NE-E. Avoid being on or under steep slopes in the alpine where natural and human triggered avalanches up to 4' deep will be come increasingly more likely. A CONSIDERABLE avalanche danger exists on all aspects near treeline and above, and on steep northerly facing slopes below. In these areas, human triggered slab avalanches involving the new snow could step down into buried persistent weak layers producing deeper, and more dangerous avalanches. Avoid avalanche terrain today including run out zones.
Blowing and drifting snow will create unstable slabs a foot or more deep on leeward slopes facing W-N-E near and above treeline. Dangerous in and of themselves, triggered wind slabs on these aspects are likely to produce much deeper and more dangerous avalanches failing on a buried persistent weak layer. Avoid all steep, wind drifted slopes.
As new snow accumulates, so will the likelihood for human triggered, soft slab avalanches on all aspects. Any avalanche triggered within the new snow has the potential to step down into a buried, persistent weak layer causing a deeper, more dangerous avalanche. Travel advice remains the same, avoid avalanche terrain.
A persistent weak layer (PWL) of faceted snow that developed during the cold dry period in mid November exists on all aspects and elevation bands in the La Sal range. Dangerous avalanche conditions exist on any slope that harbors this buried PWL including those facing south. On northerly aspects, new and wind drifted snow has added more stress to this buried weak layer, and human triggered avalanches up to 4' deep are likely. The snowpack is undergoing a severe test right now, and this process will continue into next week. Once this next load is applied, we'll have a better idea about the future of our snowpack. For now, all slopes steeper than 30 degrees should be avoided.
Road Conditions: Snow is accumulating on the road since the last plow and the top is rutted and soft. 4x4 with good tires recommended.
Grooming: LUNA groomed all trails on Friday. 9" of snow has fallen since.
No recent avalanches have been reported since Wednesday's natural cycle. Here is a list of avalanches from that event.
24 Hour Snow 5" 72 Hour Snow 9" Season Total Snow 108" Base Depth at Gold Basin 59"
Winds on Pre Laurel Peak SSE 20-25 G39 Temp 24F
Weather
A deep low pressure system moving in from the Pacific Coast is feeding warm, moist air on a southwest flow into the region. Periodic snowfall should continue through the day with 3"-5" possible. Southerly winds will blow in the 20-25 mph range with gusts in the 30's along ridge tops. High temps at 10,000' will be in the upper 20's. Snowfall will continue tonight and into tomorrow with another 4"-8" possible. Unsettled weather continues through the week.
General Conditions
Snow continues to accumulate with totals for the week now up around 30" at over 3.0" of Snow Water Equivalent. The mid-week storm re-awakened buried persistent weak layers on all aspects resulting in several large, natural avalanches. As new and drifting snow continues to pile up today, already dangerous conditions will become even more so. Avalanche terrain is to be avoided, and this means slopes steeper than 30 degrees on all aspects. Riding conditions yesterday took a turn for the weird with misty, Pacific Northwest like weather producing heavy rime, and crusting over the snow surface up to at least 11,000'. For more on that, see this great observation from Maggie Nielsen.
Snowpack and Weather Data
Gold Basin Storm Stake (10,000')
Gold Basin SNOTEL site (10,000')
SNOTEL site near Geyser Pass Winter Trailhead (9600')
Wind Station on Pre-Laurel Peak (11,400')
NWS forecast for the La Sal Mountains.
This forecast is from the U.S.D.A. Forest Service, which is solely responsible for its content. This forecast describes general avalanche conditions and local variations always occur. This forecast will be updated by 7:30 tomorrow morning.
