Provo Avalanche Advisory

Forecaster: Evelyn Lees

BOTTOM LINE

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


Danger Rose Tutorial

The avalanche danger is CONSIDERABLE (Level 3) on and below all mid and upper elevation slopes approaching 35 degrees. Sluffs and soft slab avalanches will be easy to trigger, especially on wind drifted slopes, and natural avalanches are still possible if the winds increase where you are.

The danger of a new snow slide stepping down and triggering a deep, deadly avalanche is also CONSIDERABLE (Level 3), on mid and upper elevation slopes facing northwest through southeast.

CURRENT CONDITIONS

The cold front marched right in on time yesterday afternoon, and as of 6 am:

• Cottonwoods: overnight snow 10 to 20”, storm total 2 to 3 feet, 2.5” water.

• Park City side: up to a foot overnight, storm total 1 ½ to 2 feet.

• Ogden area mountains: 8 - 12” overnight, 2’ storm total, 1.5 to 2” water

• Provo area mountains: 5-8” overnight, 1’ storm total

The west to northwesterly winds have decreased, and are currently less than 15 mph at most stations, with only the highest peaks averaging to 30 mph and gusting to 40 mph. Temperatures are in the single digits to low teens. Trail breaking and turning will be easier in drainages that received less snow.

RECENT ACTIVITY

A natural avalanche cycle occurred in Little Cottonwood between 6 and 7pm last night, and I am sure many slopes in the backcountry slid during the period of highest snowfall rates. Yesterday, easily triggered soft slabs and sluffs were reported from the Ogden area mountains south through the Cottonwood Canyons, with a few natural occurring late in the afternoon. While most were small, a skier triggered slide on SW facing Patsy Marley ran over 1000'. In the backcountry near Powder mountain, a natural class 4 hard slab from Sunday was spotted on a SE facing slope - 4' deep by 500' wide, running 2500'. This one started as a new snow slide, and stepped down to an ice crust. There was also a small wet loose avalanche cycle at the low and mid elevations.

THREAT #1
WHERE PROBABILITY SIZE TREND
      Over the next 12 hours.

The snow from Sunday through this morning has several weaknesses, and wants to move. Expect easily triggered soft slabs and sluffs on steep slopes of all aspects. Slides will be wider and much deeper than yesterday, pack a punch, and be able to entrain snow as they move down slope, so debris piles may be very deep.

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

The overnight, a short lived outburst of westerly winds averaged 20 to 25 mph, with the highest peaks gusting to 70 mph. This created wind drifts along the ridgelines, and there are reports of drifts well down into mid elevation terrain this morning. These drifts are now hidden beneath the new snow. Today, there may be a high elevation wind event, during which natural avalanches are possible. Stay aware of the terrain above you, and avoid travel on and below steep wind drifted slopes.

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

For the past 6 weeks, the deeply buried weak layers have been awakening every time we get a period of rapid loading from snow or wind. The latest example is the natural deep slab avalanche in the Ogden area mountains from Sunday’s storm. Today, a few of these monsters are possible, and will most likely be triggered in the backcountry by the weight of a new snow slide that then steps down, releasing a huge, deep unsurvivable avalanche.

MOUNTAIN WEATHER

High pressure is rapidly building into the area, and the snow should taper off by late morning. 1 to 5” of additional snow is possible this morning, with the highest amounts in the northwest flow favored Cottonwood areas. The northwesterly winds should average less than 15 mph, with gusts in the 20’s. A high elevation wind event may allow speeds in the 20 to 30 mph range, with gusts to 45, across the highest, 11,000’ terrain. Temperatures will be in the mid teens to mid 20’s. High pressure should strengthen through mid week.

GENERAL ANNOUNCEMENTS

If you trigger an avalanche in the backcountry - especially if you are adjacent to a ski area – please call the following teams to alert them to the slide and whether anyone is missing or not. Rescue teams can be exposed to significant hazard when responding to avalanches, and do not want to do so when unneeded. Thanks.

Salt Lake – Alta Central (801-742-2033)

Ogden – Snowbasin Patrol Dispatch (801-620-1017)

Provo – Sundance Patrol Dispatch (801-223-4150)

Discount Lift tickets: Ski Utah, Backcountry.com, Alta, Deer Valley, Park City, The Canyons, Wolf Mountain, Snowbasin, Beaver Mountain, Brighton, Sundance, and Solitude have donated a limited number of tickets for sale.

Wasatch Powderbird Guides flight plan.

Dawn Patrol Forecast Hotline, updated by 05:30: 888-999-4019 option 8.

Daily observations are frequently posted by 10 pm each evening.

Subscribe to the daily avalanche advisory e-mail click HERE.

UDOT canyon closures UDOT at (801) 975-4838

You have the opportunity to participate in the creation of our own community avalanche advisory by submitting avalanche and snow observations. You can also call us at 801-524-5304 or 800-662-4140, or email by clicking HERE

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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.

We will update this forecast tomorrow morning. Thanks for calling.

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.