Provo Avalanche Advisory

Forecaster: Drew Hardesty

BOTTOM LINE

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


Danger Rose Tutorial

Tricky pockets of CONSIDERABLE exist for widespread, stiff, and unmanageable hard wind slabs. They’ll be up to 2’ or more deep and will have the cohesion to propagate much wider than yesterday’s 40’. New snow instabilities may not settle out as quickly as in the recent days…..Ramp up the caution and the best bet will be on 30-35 degree wind-protected, forested, sub-alpine terrain.

CURRENT CONDITIONS

We’ve added another pretty-evenly-distributed-across-the-range 6-10” overnight on top of yesterday’s lackluster inch or two. The winds seem to not get enough of the headlines, and they’ve been pushing 25-30mph, gusting to 50. Higher anemometers are bracing 100+mph gusts. Even the underrated Tom’s Hill sensor has seen gusts into the 30’s and 40’s. Temps are generally in the mid teens. Wind and sun have damaged more of the landscape, and even the new snow is coming in a little thick around the ankles. Densities seem to be 10%+, as plates and stellars are interspersed with graupel - potentially favorable for avalanching in the new snow (geeks should check outthe northwest's Jerry Casson's paper from a couple years ago.)

RECENT ACTIVITY

You didn’t have to look hard to find and trigger very manageable new wind drifts yesterday (photo1, photo2, you-tube video), and most averaged 6-8” deep and perhaps 40’ wide. They were not confined to the high elevation ridgelines, but found, too, on mid-slope breakovers and in the lee of crossloaded deposition zones. Ski cuts and test slopes yielded good results. Cornices continue to yawn even wider and break out 5’ back upon approach.

(A correction from yesterday: in my field report from Monday, I inadvertently wrote that the arrow was pointing into the wind. It should have been “the arrow shows the direction the wind is blowing.” Thanks -)

THREAT #1
WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Stiffer wind slabs will be deposited in unusual terrain today – lower in the starting zones, around rocky outcrops, low in the chutes and gullies, and will not be the same animal as yesterday’s immediate gratification soft slabs. It may be the third rider on the slope that trips the trigger in the lateral areas of the lens.

THREAT #2
WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Periods of strong precipitation and wind this morning will heighten the danger and instability – and naturals may be possible during this time. Density breaks and intra-storm weaknesses may also persist for triggering into the afternoon.

THREAT #3
WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Cornices still pose a significant danger to the unwitting ridge walker. Give the waves a wide berth. And remember to have some sort of belay when looking to trigger them. The old let-your-buddy-hold-the-ends-of-your-ski-poles trick? May be too risky today. But if you do go out to tease the cat, put your wrists through your wrist loops so when you go over with the box-car, at least you dislocate both, not one, of your shoulders……..

MOUNTAIN WEATHER

Heavy snow and strong winds this morning will give way to snow showers and slowing northerly flow. Temps will be in the low teens. We’ll get a small break tonight into tomorrow with some light snow tomorrow ahead of a complex system for Thursday night into early Saturday. Rapid warming follows for the weekend with the longer range models hinting on a large scale storm system for the middle of next week.

GENERAL ANNOUNCEMENTS

Wasatch Powderbird Guides didn’t get out on Monday and won’t be out today. Check their operations planning page is here.

Our web site is now formatted for iPhone. You can also download a free iPhone application from Canyon Sports to display the Bottom Line. Search for Utah Avalanche on the Apple's iPhone Apps page or in iTunes.

Beacon training parks are up and running! There is one at Snowbasin, one on the Park City side at the top of Canyon’s gondola toward the Tombstone lift, one in Little Cottonwood near the Snowbird parking structure on the bypass road, and in Big Cottonwood a training park is at the west end of Solitude's lower parking lot.

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

For a text only version, the link is on the left side bar, near the top.

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).

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Your snow and avalanche observations can save someone’s life. Please let us know what you're seeing by leaving 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.

Brett Kobernik will update this advisory by 7:30 tomorrow 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.