Avalanche Advisory
Advisory: Provo Area Mountains Issued by Trent Meisenheimer for Monday - February 5, 2018 - 6:59am
bottom line

Today, we have a MODERATE danger for triggering a persistent slab avalanche on slopes that face northwest to east above 8,500' in elevation. The most suspect slopes will be the ones that are getting loaded by the wind and new snow. Human triggered avalanches 1-3' deep are possible. Additionally, shallow pockets of wind blown snow will be found along the upper elevation terrain features and will be most problematic in high consequence terrain. Lastly, damp push-alanches are possible in steep low to mid-elevation sheltered slopes that have remained warm for the past several days.




special announcement

The latest UAC podcast - "Recreating Like a Pro - A Conversation with IFMGA guide Anna Keeling" is live. This podcast will be ideal for anyone looking to pick up some tips and tricks from a professional mountain guide for recreating in the winter backcountry environment.


New blog post - Stacking the Deck - a Hindsight 20/40 story

current conditions

Mostly cloudy skies this morning with light snow showers across the northern mountains. Areas favored by a northwest flow have picked up 1-3" of snow with (0.10" to 0.36") snow water equivalent. West and northwest winds continue to be strong across the high terrain with average speeds of 20-30 mph gusting into the 50's. Mid elevation winds are 15-25 mph gusting into the 30's. Current upper elevation temperatures are in the 25-30°F range. Lower elevation trailheads are in the mid to low 40's °F. The rain/snow line is currently around 8500' feet in elevation.

A few inches of dense, wind driven snow can go a long way for our weathered snow surface. Riding and turning conditions will be improving today and into tomorrow as a few more inches of snow stack up. The southerly terrain will be dust on crust, while the northerly facing terrain will be a mix of powder, rime crust, and wind crusts.

recent activity

None. Here is a LIST to all the observations in the SLC mountains.

Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 12 hours
description

With each loading event we see this dragon come back to life - It's hard to say how much wind or snow (weight) it will take to re-activate this beast. Looking back to the Meadows avalanche from January 26th we had a new load of 2-6" inches of snow with about 0.5" of SWE. This was enough of a load to cause human triggered avalanches. Our weak and fragile snowpack just can't handle a lot of weight.

Today, we will continue to add more weight and stress to the snowpack as a series of small storms impact northern Utah. Currently, many stations have reported (0.1" to 0.36") snow water equivalent (load to our snowpack). By the end of the day we could see this add up to roughly the same snow and water amounts that led to the Meadows Close Call , West Willows Avalanche , and Lavina Creek slides. The most suspect terrain will be mid to upper elevation northwest through east facing terrain that is being loaded by the wind and new snow. Avoid - rocky, steep, and shallow areas if you decide to push the slope angles. Set your-self up for success by choosing terrain with clean run-outs.

This year, I've continued to avoid this terrain all together by keeping my slope angles to 30° and avoiding terrain that's above and adjacent to me. I simply do not trust the snowpack. I am yet to ride anything steep (greater than 30°) that faces the north half of the compass. Maybe, some would call me too conservative (that's okay) I am in it for the long run.

Avalanche Problem 2
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

As the strong west and northwesterly winds continue across the high elevations it will grab whatever snow is available for transport - depositing the snow on the lee side of ridges and terrain features. It only takes a few inches of snow to create new sensitive wind drifts. Avoid rounded, pillowy snow, especially if it sounds hollow like a drum.

Heads up - If you trigger a small wind slab avalanche in the northerly facing terrian it has the potential to step down into deeper weak layers, creating a larger slide.

weather

We remain under a northwest flow today and tomorrow. Winds will continue to blow from the west and northwest with speeds of 20-30 mph gusting into the 30's and 40's across the mid to high elevation terrain. Snow showers will be off and on, with times of riming. Temperatures are expected to cool slightly this afternoon and the rain/snow line will be dropping from 8500' down to 6000' later today. Tonight and tomorrow will be the best chance for snow as a another trough swings by. lets hope for 5" to 9" inches of total snow by Tuesday evening before drying out midweek.

general announcements

CLICK HERE FOR MORE GENERAL INFO AND FAQ

The UAC has new support programs with Outdoor Research and Darn Tough. Support the UAC through your daily shopping. When you shop at Smith's, or online at Outdoor Research, REI, Backcountry.com, Darn Tough, Patagonia, NRS, Amazon, eBay a portion of your purchase will be donated to the FUAC. See our Donate Page for more details on how you can support the UAC when you shop.

Benefit the Utah Avalanche Center when you buy or sell on eBay - set the Utah Avalanche Center as a favorite non-profit in your eBay account here and click on eBay gives when you buy or sell. You can choose to have your seller fees donated to the UAC, which doesn't cost you a penny

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.