Avalanche Advisory
Advisory: Moab Area Mountains Issued by Eric Trenbeath for Wednesday - December 17, 2014 - 6:46am
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The avalanche danger is MODERATE today for triggering a recently buried persistent slab on upper elevation terrain steeper than 35 degrees on slopes with a NW-N-E aspect.




current conditions

The mountains only picked up 3-4" of new snow from the Wednesday-Thursday event, but combined with totals of up to 16" from last weekend, conditions have improved remarkably. Winds have also been relatively behaved this week, and snow surface conditions are mostly powder. Keep in mind however, that the snowpack is still quite shallow, and there are many objects lurking just below the surface that could ruin the rest of your season. There is 22" of snow at the Geyser Pass Trailhead, and 32" in Gold Basin.

NW winds have been mostly light overnight, barely gusting into the teens, and are currently in the single digits. The temperature on Pre Laurel is a frigid 7 degrees, and it is 18 at the trailhead.

Mountain weather conditions at 11,700' on Pre-Laurel Peak.

Snow totals at Geyser Pass Trailhead.
Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

The snow that fell over the past week has largely settled into place, and we are now back to concerns over the ever present persistent slab. November snow is turning to facets, or weak sugary snow, and we are now starting to get a load on top. In some cases, old stiff slabs overly these facets, and they are now covered by anywhere from 1-2' of new snow. There is also a very weak layer of mid pack faceting associated with a crust. The concern now is triggering a slide on one off these buries weaknesses. You are most likely to encounter this problem on slopes steeper then 35 degrees on upper elevation slopes with a NW-N-E aspect.


Weak, faceted grains at the bottom of the pack.
weather

Today should be a beautiful day in the mountains. A moist, NW flow will move into the area by Saturday keeping us under mostly cloudy skies with a chance of snow over the weekend. A weak high pressure ridge will build for the first part of the week, with what looks like another system arriving just in time for Christmas.

Today: Areas of fog before 9am. Otherwise, mostly sunny, with a high near 26. West northwest wind around 5 mph.

Tonight: Mostly cloudy, with a low around 15. West wind around 5 mph.

Saturday: A slight chance of snow between 9am and 3pm. Partly sunny, with a high near 29. South wind 5 to 10 mph becoming north northeast in the morning. Chance of precipitation is 20%.

Saturday Night: A 20 percent chance of snow after 4am. Mostly cloudy, with a low around 21. West northwest wind 10 to 15 mph becoming north northeast after midnight.

Sunday: A 30 percent chance of snow, mainly after 11am. Partly sunny, with a high near 33. Breezy, with a north wind 15 to 20 mph becoming west northwest in the morning. Winds could gust as high as 30 mph.

Sunday Night: A 30 percent chance of snow, mainly after 11pm. Mostly cloudy, with a low around 23. Blustery.

Monday: A 20 percent chance of snow. Partly sunny, with a high near 33. Breezy.

Monday Night: Partly cloudy, with a low around 20. Blustery.

Tuesday: Mostly sunny, with a high near 33. Breezy.

Tuesday Night: Partly cloudy, with a low around 21.

Wednesday: Mostly sunny, with a high near 34.

Wednesday Night: A chance of snow. Mostly cloudy, with a low around 19. Breezy.

Christmas Day: A chance of snow. Mostly cloudy, with a high near 21. Breezy.

general announcements

The road to the Geyser Pass Trailhead was plowed again yesterday morning. 

Matt and Jesse took the roller out and packed in the grooming track on the lower mountain, into Gold Basin, and up to Geyser Pass on Monday. The mountain won't be groomed again for the weekend as the roller needs to be brought down for repairs. 

I will update this advisory again on Sunday morning, or sooner if conditions warrant.