Wasatch Cache National Forest
In partnership with: Utah Division of State Parks and Recreation, The Friends of the Utah Avalanche Center, Utah Department of Emergency Services and Homeland Security and Salt Lake County.

“keeping you on top”

AVALANCHE ADVISORY

Tuesday, April 08, 2008 7:30 am
Good morning, this is Evelyn Lees with the Forest Service Utah Avalanche Center with your backcountry avalanche and mountain weather advisory. Today is Tuesday, April 08, 2008 and it’s about 7:30 am.

Current Conditions:

Under mostly clear skies, temperatures are in the wintry single digits to low teens this morning. The northwesterly winds are light, generally less the 10 mph, with even the highest peaks only gusting into the 20’s. Yesterday morning, it was zero to 16 inches in about 4 hours, of incredible “Oh, my gosh” Utah powder. Storm totals were 10 to 17 inches in the Cottonwoods, on the Park City side, and north through about Farmington Canyon, after which they rapidly tapered to zero. Parts of the Provo mountains received up to 7” of snow. The clouds tried to do their part yesterday, and some slopes did avoid heating by the sun. In other drainages, the snow turned to instant mashed potatoes and is crusted.

Snow and Avalanche Discussion:

The forecast new snow avalanche activity progressed with Swiss-like precision yesterday – natural new snow sluffs and soft slabs occurred during the period of peak precipitation intensity, followed by easily triggered sluffs and soft slabs, all averaging about 6-12“ deep by 50 feet wide. (One person took ride and was partially buried on south facing Little Superior.) And finally, there was just enough sun and heating to create a wet snow cycle in some drainages, with both natural and easily triggered loose wet sluffs. These packed the most punch of the day, and were the most dangerous.

This morning, a full on assault by the sun is likely, which will cause the avalanche danger to rapidly increase through about noon. As the intense spring sun heats the cold new snow, the snow will become very sensitive to slope cuts and natural avalanche activity may be possible. First easterly, then southerly facing slopes will heat up. As the high, thin clouds move in, greenhousing will heat the snow on just about every aspect, with almost no slope immune. Damp sticky snow and roller balls will be an early indication it’s time to get off the steep slopes, and onto lower angle slopes or a cooler aspect. While slope cuts could be effective, these wet sluffs are more dangerous, and can easily catch, carry, and bury you beneath their cement like snow. Watch out for backcountry travelers below and above you, and avoid any terrain traps like gullies. By early afternoon, the clouds will hopefully thicken enough to reduce heating and sensitivity.

On the steeper, mid and upper elevation northerly facing slopes, dry snow sluffs and soft slabs will be possible, especially on any wind drifted slope. These should be manageable for the experienced traveler with careful slope cuts. In a few isolated places, there is a thin, weak sun crust beneath the new snow. If this crust fails, the resulting avalanche could be wider or break out above you.

Bottom Line for the Salt Lake, Park City, Provo and Farmington Canyon area mountains: The avalanche danger will rapidly increase to MODERATE this morning with sun and daytime heating. Wet sluffs and wet slab avalanches will be easily triggered, first on steep easterly and southerly facing slopes, then west and north. Depending on the balance of sun, clouds and wind, the danger of wet slides could rise to CONSIDERABLE, with natural avalanches possible. There is also a MODERATE danger for sluffs and shallow soft slabs on steep slopes with dry snow.

Bottom Line for the northern Ogden area mountains: With 2 inches or less of new snow, the avalanche danger is generally LOW, and will rise to MODERATE with daytime heating in localized areas on slopes of about 35 degrees and steeper.

Mountain Weather:

Another Pacific storm system is on the way and clouds will increase throughout the day, with light snow showers possible by late afternoon. Winds are in the process of shifting to the southwest, and will remain light, generally in the 5 to 15 mph range. Temperatures will warm into the upper 30’s at 8,000’ and to near 20 at 10,000’. Snowfall will increase after midnight, and another early morning special could produce 8 to 15 inches of fresh powder by midday Wednesday, with temperatures cooling back into the teens at 10,000’. Partly cloudy skies with a few snow showers on Thursday, followed by high pressure with rapidly warming temperatures Friday through the weekend.

Announcements

The Wasatch Powderbird Guides didn’t get out yesterday and today they will be in Mineral, Cardiff, Days, and Silver with home runs through White Pine and Grizzly. For more detailed information please call (801) 742-2800 or go to their daily blog.

If you want to get this avalanche advisory e-mailed to you daily click HERE.
UDOT highway avalanche control work info can be found by calling (801) 975-4838.
Our statewide tollfree line is 1-888-999-4019 (early morning, option 8).

Watch video tututorials and fieldwork from UAC staff at our YouTube channel.

The UAC depends on contributions from users like you to support our work.  To find out more about how you can support our efforts to continue providing the avalanche forecasting and education that you expect please visit our Friends page.

If you see any avalanches or interesting snow conditions, please leave us a message at (801) 524-5304 or 1-800-662-4140, or email us at [email protected]. (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.

I will update this advisory by 7:30 on Wednesday morning.