Moab Avalanche Advisory

Forecaster: Dave Medara

BOTTOM LINE

Danger by aspect and elevation on slopes approaching 35° or steeper.
(click HERE for tomorrow's danger rating)


Danger Rose Tutorial

Click here to see the newly revised North American Avalanche Danger Scale.

Continued Dumpage. 21-23" of pretty heavy powder in the La Sals. Only 6-8" measured in the Abajos, but reports from backcountry skiers down there indicate more. More snow on the way. Expect to find HIGH avalanche danger in the La Sal and Abajo Mountains on slopes steeper than 30 degrees. Danger may be a bit less in the Abajos, but with conflicting snow totals being reported and confirmed massive amount in the La Sals we're taking the conservative line.


CURRENT CONDITIONS

This storm is turning into another massive one for Southeastern Utah, especially in the La Sals. Snowfall took the night off but has now resumed with favorable winds (for more snow...) out of the south. Great conditions are available for skiing and riding, if you can get up to the mountains. Snowmachiners, bring your back braces and be ready for some deep heavy stuff. We've been averaging over 10% density through this storm. With temps dropping densities should go down making for a nice top layer of lighter snow. So far, we've measured 21" at the La Sal SNOTEL site, 23" or so in Gold Basin but only 6-8 inches in the Abajos. Unofficial reports from the Abajos suggest more snow than what we are measuring.

Roads have not been plowed so expect a long walk into Mountain Trailheads until San Juan County can get up there to clear the roads. People were only making up as far as the cattle guard below the Aspen line on the Geyser Pass Road. Today may be a good day to head down to the Old Blue Mountain Ski resort with a shorter approach and a little less new snow and little avalanche exposure.

Grooming on the La Sal Nordic Track will have to wait until next week when this storm tapers off.


RECENT ACTIVITY

No visibility as of yet for avi observations. Widespread collapsing and cracking.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 48 hours.

Click here to see the newly revised North American Avalanche Danger Scale.

We're well over threshold values of snow, water equivalent and winds for large avalanches to run in the mountains of SE Utah, particularly in the La Sals. Mother nature has been pouring it on for the last 2 days and with nearly two feet of new snow at only 9800 feet in elevation (remember the higher you go the more it is likely to snow) you don't need to be a snow scientist to recognize the danger here. The high density of the new snow increases the likelihood of slab formation. Natural and Human triggered avalanches are pretty much a certainty, so consider this if you decide to head into the Mountains. It is an absolute MUST to limit your exposure to slopes less than 30 degrees in steepness.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

We still have some pretty serious issues with our "old" snow. First is a buried layer of surface hoar that is now about 2-3 feet below the surface of the new snow. This layer continues to be reactive in snowpit tests. Tuesday I dug a lot of pits trying to determine the extent and distribution of the surface hoar layer and found it to be on open NE-NW facing slopes at and below treeline. No surprise there. Unfortunately what I found where the surface hoar layer didn't exist, was a layer of near-surface facets at the same level in the snowpack, that was equally reactive in snowpit tests. Another classic SW snowpack situation. Combine that with depth hoar that is can still be found in the lower third of the snowpack (producing the dramatic collapses still being felt in thinner snowpack areas) and we've got all three of the classic types of persistent weak layers at play in our SE Utah snowpack. As always approach steep slopes with respect here in SE Utah.


MOUNTAIN WEATHER

National Weather Service Forecast for 10,000 Ft. :

Today:

Snow. High near 18. East northeast wind around 5 mph becoming calm. Chance of precipitation is 90%. Total daytime snow accumulation of 3 to 7 inches possible.

Tonight:

Snow. Low around 8. West wind around 5 mph. Chance of precipitation is 100%. New snow accumulation of 3 to 7 inches possible.

Monday:

Snow likely, mainly before 11am. Mostly cloudy, with a high near 16. Calm wind becoming north northwest between 5 and 10 mph. Chance of precipitation is 60%. New snow accumulation of less than one inch possible.

Monday Night:

Partly cloudy, with a low around 1. Northeast wind between 5 and 10 mph.

Tuesday:

Mostly sunny, with a high near 22. North northeast wind around 5 mph.

Tuesday Night:

Partly cloudy, with a low around 9.

Wednesday:

Partly sunny, with a high near 25.

Wednesday Night:

A slight chance of snow. Mostly cloudy, with a low around 14.

Thursday:

A slight chance of snow. Mostly cloudy, with a high near 25.


GENERAL ANNOUNCEMENTS

We would like to thank the hard working volunteers at the Friends of the La Sal Avalanche Center. Without their help the center would not meet it's funding or staffing requirements. Thanks all! If you would like more information about donating to the Friends or simply helping out, click here..

This advisory will expire in 48 hours.


This information does not apply to developed ski areas or highways where avalanche control is normally done.  This advisory is from the U.S.D.A. Forest Service, which is solely responsible for its content. This advisory describes general avalanche conditions and local variations always occur.


This advisory provided by the USDA Forest Service, in partnership with:

The Friends of the Utah Avalanche Center, Utah Division of State Parks and Recreation, Utah Division of Emergency Management, Salt Lake County, Salt Lake Unified Fire Authority and the friends of the La Sal Avalanche Center. See our Sponsors Page for a complete list.