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 MODERATE on mid and upper elevation, steep northwest through easterly facing slopes for both new drifts of windblown snow and the isolated chance of triggering a larger slide on a more deeply buried weak layer. Slopes less steep than about 35 degrees, southerly facing slopes and low elevation slopes generally have a LOW avalanche danger. (see the Danger Ratings Tutorial and the Danger Rose Tutorial)


CURRENT CONDITIONS

Under partly cloudy skies, temperatures are mostly in the mid 20s, with a band of warmer air at the mid elevations in the balmy mid 30s. Yesterday’s gusty southwesterly winds have calmed down into the 15 to 20 mph range at most stations, with only a few isolated peaks gusting to 40 mph. Soft snow is a scarce commodity these days, but patches do exist on sheltered, mid and upper elevation northerly facing slopes. Many of the steeper sunny slopes have a refrozen icy, rock hard crust, and potential “slide for life” conditions exist.


RECENT ACTIVITY

The only report of avalanche activity yesterday was a cornice triggered wind slab, 2 ½ feet deep by 75’ wide on a steep, wind loaded northeasterly facing slope along the Park City ridge line.


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

The two avalanche issues today are the new drifts from yesterday’s stronger southwesterly winds and the continuing chance of triggering a deeper, wider slide on a layer of weak facets. The wind drifts will be most common along the high ridges on slopes facing north through east, with some drifting off ridgelines around sub ridges and gully walls. Drifts will be hard, smooth, rounded and may be hollow sounding.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

While facets exist in the snow pack almost all the way around the compass, the current problem areas are the mid and upper elevation slopes facing northwest through east. Several potential weak layers exist, including on slopes that have slid one or more times this winter. If you choose to ski and ride the steep, shadier slopes, these dangerous avalanche conditions require skill in evaluating the snow and terrain. On the sunny, southeast through westerly facing slopes, there are buried faceted weak layers, too. However, any where the snow surface has cooled and is now a stout ice crust, the deeper facet layers have been rendered temporarily powerless.


MOUNTAIN WEATHER

It looks like we may be treated to one more non-event, before a pattern change next week finally brings more reasonable snow amounts. Today, there will be increasing clouds, with light snow flurries possible by afternoon. Total accumulations of a trace to a few inches are possible by Thursday afternoon. Temperatures today will be in the mid 20s and 30s, with the winds remaining from the southwest, averaging 10 to 15 mph. A few of the highest peaks may average closer to 20 mph, with gusts to 40. High pressure will build right back in late Thursday for the weekend. But there is finally some good news - the models have been consistent in a change to a more moist, westerly flow next week.


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.