A huge snow data discrepancy has occurred this morning. Most sites are showing only an inch or two overnight with one anomalous reading of more than a foot. If you arrive at the parking lot this morning and find 8" or more of new snow, the avalanche danger will be HIGH. Otherwise, incremental loading today will slightly increase what is already a CONSIDERABLE avalanche danger. This danger exists on steep, wind drifted slopes near treeline and above that face W through N through E. Dangerous, human triggered avalanches, failing on a buried persistent weak layer 1'-4' deep are likely in these areas and slopes steeper than 30 degrees should be avoided. Terrain on the southern half of the compass offers MODERATE to LOW danger. In general, the danger increases with elevation on these aspects.
Blowing and drifting snow continues to create slabs on northerly aspects. Though fresh deposits of wind drifted snow are a concern, the primary issue is continued loading on the buried persistent weak layer. Avoidance of steep, northerly facing slopes is the only realistic strategy at this time.
A persistent weak layer of faceted snow that developed during the cold dry period in mid November is now present on all aspects. The condition is most dangerous and wide spread on slopes facing the north half of the compass, where wind drifted snow has built thick slabs on top. On the south side of the compass it is more hit and miss due to scouring and low snow conditions on these aspects. This persistent weak layer is settling in and will be with us for awhile so plan on avoiding slopes steeper than 30 degrees, especially those that face NW-N-E, for the foreseeable future.
Photo illustrates the obvious poor snowpack structure on a NE aspect. As more snow is piled on top, stress on the weak snow will increase, as will the likelihood of triggering deeper and more dangerous avalanches.
Photo illustrates obvious weak layer of facets on a W aspect. What's lacking here is dense, cohesive slab on top. But that's sure to come, and the weak layer isn't going away.
Wow, that was a blast! Thanks to everyone for turning out and making the 1st Annual UAC Moab/LUNA Winter Kickoff Party a huge success! Music was played, prizes were given, skis were waxed, and a great time was had by all! A huge shout out to the band, our local crew of observers/volunteers, and our friends at Moab Gear Trader for making this event possible!
Road Conditions: Grand County has plowed the road to Geyser Pass Trailhead. The road surface is snow packed over dirt. AWD and good tires are recommended.
Grooming: The Geyser Pass Road above the winter trailhead closes on Dec 15. Grooming will commence after that.
24 Hour Snow 0" 72 Hour Snow 0" Season Total Snow 55" Base Depth at Gold Basin 30"
Winds on Pre Laurel Peak SSE 15-20 Temp 21F
Weather
I'm facing some serious data discrepancy this morning with the storm stake reporting a foot of new, and both SNOTEL sites showing nothing as of 6:00 am. Given the timing of the storm I'm going to have to go with the SNOTEL reports but if you get up there and find a foot of snow, the danger will be HIGH today.
A Pacific storm system is on our doorstep and we should see some pretty good snowfall this morning, tapering off later today. 4"-8" are possible. Southerly winds that have been cranking in the 30-40 mph range for the last 24 hours will finally back off into the 15-20 mph range. A chance of snow showers will linger into Tuesday. Overnight temps will crater into the single digits, and will barely climb into the lower teens tomorrow. The system moves on by Tuesday night bringing sunny skies on Wednesday and cold temps through the week. The weekend storm system has vaporised into a cut off low that is diving far south.
General Conditions
The snowpack has quickly become eerily quiet and in our travels over the weekend we didn't experience any collapsing or whumphing. A poor snowpack structure still exists however, and the entire snowpack beneath the November 28 storm is loose, weak, and faceted. Incremental loading from new and drifted snow will keep us in a dangerous state where the signs of instability aren't obvious but the danger remains the same or slightly elevated. On wind drifted northerly aspects, slabs 1'-4' thick exist over this weak, faceted layer and deepa and dangerous, human triggered avalanches are likely in these areas.
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.
If you are getting up into the mountains please submit an observation and let us know what you are seeing!
Get the most recent observations here.
This detailed snowpit illustrates my findings on a NE aspect at 11,200'.
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.
