Logan Avalanche Advisory

Forecaster: Toby Weed

BOTTOM LINE

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


Danger Rose Tutorial

On most slopes in the region there's a LOW danger, and avalanches generally are unlikely.  However, a MODERATE danger exists in some areas , meaning there are dangerous avalanche conditions in some terrain features.  In the heat of midday, you could trigger wet avalanches on some steep sunny slopes with saturated snow.  The danger of deadly deep slab avalanches is gradually diminishing, but the continued existence of weak sugary or faceted snow near the ground indicates that they're still possible, mainly in upper and mid-elevation areas with thinner overall snow cover.  Isolated, triggered wind-slab avalanches are also a possibility on a few wind-drifted slopes steeper than about 35 degrees.

Evaluate the snow and terrain carefully, and use wise travel techniques....


CURRENT CONDITIONS

Boon-docking is good at all elevations on generally supportable snow, but you might bog down in moist snow on some sunny mid-elevation slopes today.  You’ll probably have to stop and open up the hood once or twice due to the warm daytime air temperatures in the mountains…

Most slopes in the region are now sun-crusted, wind-blasted, or rimed. (1-15-09 photos)  But frost and the process of water vapor sublimation is re-crystallizing the snow surface and you can find some nice “loud powder” conditions in sheltered shady terrain.

It's currently a balmy 28 degrees at the Campbell Scientific weather station on Logan Peak at 9700', and the wind sensor is reading a consistent 15 mph northeast breeze.  Expect 9000' high temperatures in the lower 40s today


RECENT ACTIVITY

Snowmobilers reported a fresh avalanche in the Western Uintas yesterday....

Other than a few loose wet avalanches on steep sunny slopes, no significant new avalanches have been reported or observed in the backcountry elsewhere in the Wasatch, or in the Logan Area in the last week....


THREAT #1

WHERE PROBABILITY SIZE TREND
      Over the next 8 hours.

Wet avalanches aren't too common around here in mid-January. But they are possible today, with mountain temperatures well above freezing and intense solar heating in bowls facing just the right direction and on slopes with just the right tilt.


THREAT #2

WHERE PROBABILITY SIZE TREND
      Over the next 24 hours.

The danger of deadly deep slab avalanches is gradually diminishing, but weak sugary or faceted snow is still present at the very bottom of the snowpack...In many areas this weak snow has been compacted and compressed into the terrain by the tremendous load of the overlying slab.  But there might still be exceptions, especially in shallower areas and where the faceted basal layer makes up a higher percentage of the overall snowpack. 

There are also hard wind slabs on many slopes in the region. Most of these are solidly bonded to the underlying snow...But you could perhaps still trigger wind slab avalanches on a few very steep, exposed slopes and in or around terrain features like gullies or cliff-bands....


MOUNTAIN WEATHER

Expect sunny conditions in the mountains today, with high temperatures above 40 degrees at the mountain tops...Haze and smog will become trapped in Cache Valley as a temperature inversion continues under a solid high pressure system.   The inversion will only get stronger in the next few days, with fair and mild weather in the mountains and cold fog and poison smog in the valleys...   Cooler temperatures are possible mid-week, but the next possibility of a storm holds off until around next weekend.


GENERAL ANNOUNCEMENTS

New***   Click HERE for the online version of the Know Before You Go video.

The Utah Avalanche Center depends on contributions from users like you to support our work....You can support the Utah Avalanche Center and get discount lift tickets to  Beaver Mountain (here).  All proceeds from sales will support us through the Friends of the Utah Avalanche Center....

Also the friends still have a few items left over from the Logan fundraiser and you can pick up a few killer deals right now..Here are the items that are still available: -

(2) One day passes to Park City Powder Cats to be used during January or March and before April 15th, 2009.  Retail value is $449 each. Suggested Donation: $225 each

-Men's Medium Patagonia Figure 4 Jacket Grey    Suggested Donation: $95

-Yamaha Leather Snowmobile Jacket Men's Medium     Black with Blue marks   Suggested Donation: $100

100% of your donation will support the Utah Avalanche Center.  Email loganavalanche@gmail.com if you are interested in any of these items.

The information in 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. 

I will update this advisory by 7:30 Monday morning.


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.