Provo Avalanche Advisory

Forecaster: Bruce Tremper

BOTTOM LINE

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


Danger Rose Tutorial

The danger is mostly MODERATE with pockets of CONSIDERABLE danger on steep slopes that were loaded with wind-drifted snow on Friday night. You will find these slopes mostly along the upper elevation ridges on slopes that face north west, north, northeast and east. Since they are covered by new snow, they are difficult to see, but those with good avalanche skills should be able to feel them by regularly digging down with their hand to investigate.


CURRENT CONDITIONS

Yesterday, an additional foot of new snow fell in the Ogden area mountains from lake effect snow while very little new snow fell in other areas. This gives a storm total of two feet to the Ogden area mountains and around a foot to other areas. Snow is very low density. This morning, temperatures are still chilly, around 10 degrees and the ridge top winds are blowing 20 mph from the south.


RECENT ACTIVITY

A tragic accident occurred yesterday inbounds at the Snowbird Resort. A 27-year-old woman was killed in an avalanche on a steep, northwest facing slope on Baldy around 10,500'. She was buried for 50 minutes and found by probe line. Our condolences go out to the loved ones and to the Snowbird Ski Patrol. Snowbird if famous for its state-of-the-art avalanche control program, so it goes to show that avalanche accidents can happen anywhere and to anyone. In-bounds avalanche fatalities are very rare. There have only been five inbounds avalanche deaths in Utah since 1950 versus 61 lightning deaths.

Another accident, but with a happier ending, occurred in a backcountry area near the Canyons Resort. One person triggered an avalanche and was taken into trees. He was injured and could not walk so his friends evacuated him to the flats of Red Pine lake below where professional rescuers could reach him. There were several other triggered avalanches in the Salt Lake area mountains but with no one caught, one near Alta, one in Meadow Chutes of Silver Fork and there were rumors of a couple others but we have no information on them. If you know of any others, please let us know by calling or filing out the observation form on our home page.  Finally, there was one, smaller, triggered avalanche at Snowbasin on Saturday in a closed area but no one was caught.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

With all these triggered avalanches seemed to occur where the strong, southwesterly winds loaded snow into downwind terrain on Friday, before they were covered up by a foot of light snow on Saturday. In places out of the wind, the light, new snow just doesn't seem to weight enough to make the buried weak layers sensitive. So it's an especially tricky situation because the old wind slabs are covered up and invisible.

It's also especially tricky because Sunday the backcountry was swarming with hungry powder hounds. Because only the upper elevation north through east facing slopes have enough of a base so you don't hit rocks, everyone was concentrated into the same, postage-stamp terrain, the exact same terrain that was loaded by the strong winds on Friday night, and the exact same terrain underlain by very weak, fragile, faceted snow. Finally, with the addition of more snow this afternoon, it could further overload these weak layers.

If you're interested in the conditions that caused these slides, we have an excellent photo gallery and field report we posted on yesterday's advisory by Leigh Jones, Wendy Wagner and Ian Havlick from the Monitors, which was very near the accident on Sunday. I also have a Youtube video of my field work yesterday in Silver Fork, which shows a non-wind loaded snowpack.


MOUNTAIN WEATHER

The cold, closed low has passed south of us, but it is bring moisture into northern Utah from the south and we should see 6 inches to a foot of additional snow by Tuesday morning. Most of the snow should come this afternoon and evening. Ridge top winds should blow 15-20 from the southeast with ridge top temperatures in the mid teens and an overnight low around 10 degrees. Then, we have continued scattered snow showers for Tuesday and Wednesday.

The extended forecast calls for a very cold storm for the weekend, which will likely be too cold to give us much additional snow unless we can squeeze some out of it when the cold front passes.


GENERAL ANNOUNCEMENTS

If you want to get this avalanche advisory e-mailed to you daily click HERE.

 UDOT highway avalanche control work info can be found by calling (801) 975-4838. Our statewide toll free line is 1-888-999-4019 (early morning, option 8).

The UAC depends on contributions from users like you to support our work.  To find out more about how you can support our efforts to continue providing the avalanche forecasting and education that you expect please visit our Friends page.

If you’re getting out and see anything we should know about please let us know.  You can leave a message at (801) 524-5304 or 1-800-662-4140, or email us at uac@utahavalanchecenter.org. (Fax 801-524-6301).

The information in this advisory is from the U.S. Forest Service, which is solely responsible for its content.  This advisory describes general avalanche conditions and local variations always occur.

Drew Hardesty will update this forecast by 7:30 on Tuesday morning.


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.