Provo Avalanche Advisory

Forecaster: Drew Hardesty

SPECIAL ANNOUNCEMENT

There is a Women’s Snow and Avalanche round table tomorrow evening,Tuesday Feb 21,at the Sandy REI, discussing current snow and avalanche conditions and careers in the snow and avalanche industry. Please register at REI HERE.


BOTTOM LINE

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


Danger Rose Tutorial

We have a mostly Moderate danger with the storm snow instabilities. Shallow human triggered and natural loose sluffs are likely in all of the steepest terrain at the mid and upper elevations. Sensitive but shallowish new wind drifts will be commonplace along the high lee (mostly east-facing) terrain. Isolated pockets of Considerable hazard for triggering 2-5’ deep hard slabs remain on west through north through east facing terrain at the mid and upper elevations.


CURRENT CONDITIONS

Skies are partly cloudy. Winds are generally light to moderate from the west and northwest. Temps are in the low single digits up high with mercury in the mid-teens at the trailheads. Storm totals are roughly 6-8” in upper Little Cottonwood and the Ogden and Provo mountains. Big Cottonwood and the Park City mountains received 3-4”. Densities are in the 5-7% range.


RECENT ACTIVITY

Avalanche activity remained primarily within the new snow. We had plenty of reports of natural and human triggered loose snow avalanches along with a smattering of shallow soft slabs along the higher elevations. My own party in White Pine of LCC triggered two shallow pockets – less than a foot deep and only 10’ wide – on mid-elevation roll-overs that broke into the weak snow from the 1st week of February. We also received a report of a decent debris pile on the Guardsman road above Bonanza Flats – and we’ll look to gather more info on this today.

UDOT Forecaster Bill Nalli intentionally triggered a 6" deep new wind slab that propagated 50' wide on freshly buried surface hoar late last week. This on a steep east facing slope at 8800'.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

We’ll continue to see sluffing in the cold smoke on a variety of aspects in the steep upper elevations. Any direct sun will also bump the potential for these shallow loose snow slides. These are very manageable avalanches – shallow, and not packing much punch – but can easily trip up the unwary skier or rider, leading to problems if above unforgiving terrain.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

Yes, the winds are generally light now, but for 8 hours overnight the west to northwesterlies blew in the 20-30mph range. Steep northeast to southeast facing slopes along the ridgelines will have their fair share of soft new wind drifts that will be touchy and sensitive to human weight. They will also be manageable to those with experience and training. As with the loose snow avalanches, ski and slope cuts and proper use of terrain should provide good info for slope specific snow assessment.


THREAT #3

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

It remains a low-probability high consequence game. We continue to see a great variability in snow stability test results – which still include full propagation within the depth hoar 3-5’ down. The weak basal snow is most widespread on mid and upper elevation slopes facing northwest through north through east. Likely trigger points include shallow snowpack areas or thin rocky slopes.

Trent Meisenheimer put together an excellent tutorial on the Propagation Saw Test - a good tool in the toolbox to help determine deep slab instability. Trent has been an invaluable asset to the UAC this year assisting in the Uintas and the Plateau...along with providing countless avalanche presentations this season.


MOUNTAIN WEATHER

We’ll have a bit of a break today before the skies fill again with clouds ahead of a series of storms starting tomorrow through the rest of the week. Should be a different ballgame altogether as – starting tomorrow - we’ll likely see a few inches of low density snow tomorrow followed by rising rain/snow lines, increasing snow densities and strong northwesterly winds. The avalanche danger will rise accordingly by mid-week through the weekend.


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)

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

Twitter Updates for your mobile phone http://utahavalanchecenter.org/twitter)

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

Wasatch Powderbird Guides does daily updates about where they'll be operating on this blog http://powderbird.blogspot.com/ .

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

Donate to your favorite non-profit –The Friends of the Utah Avalanche Center. The UAC depends on contributions from users like you to support our work.

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.