Advisory: Logan Area Mountains 	
Issued by Toby Weed for January 13, 2014 - 6:43am

There is a HIGH or Level 4 danger, and large and destructive avalanches are likely on drifted 
slopes in the backcountry. Triggered wind slab and very dangerous deep slab avalanches are 
likely on steep drifted slopes, and large natural avalanches are still possible today. Avoid 
travel in avalanche terrain today, and continue to stay off of and out from under steep slopes 
and obvious or historic avalanche paths.

THIS AVALANCHE WARNING IS FOR THE MOUNTAINS OF NORTHERN AND CENTRAL UTAH, TO INCLUDE THE WESTERN 
UINTA MOUNTAINS. VERY DANGEROUS AVALANCHE CONDITIONS EXIST THROUGH TODAY...AVOID BEING ON OR 
BENEATH STEEP MOUNTAIN SLOPES...AS AVALANCHES MAY BE TRIGGERED LOW ON THE SLOPE AS WELL.

The Tony Grove Snotel at 8400' reports well over a foot of new snow containing 1.6" of water in the 
last 24 hours. The station picked up 4.5" of water in the last 5 days, since January 8. It's 
currently 22 degrees and there is 59 inches of total snow on the ground, containing 89% of average 
water content for the date. It's 16 degrees at the 9700' Logan Peak weather station and the wind 
sensor appears to be rimed or covered by ice. West winds have diminished somewhat overnight at 
the Hwy 89 Logan Summit weather station, after posting average wind speeds close to 40 mph yesterday 
with gusts in the upper 50s. Very dangerous avalanche conditions exist in the backcountry, with 
drifted and inverted heavy new snow, difficult trail-breaking, and safe riding limited to lower 
angled meadows and packed trails. The heavy new snow from the past several days accumulated and 
was drifted onto slopes with widespread very weak preexisting sugary or faceted snow....

A Utah rider triggered and was caught, carried and fully buried by a very large hard slab avalanche 
north of the Idaho State Line. The 3 to 5 foot deep and perhaps 500' wide avalanche failed on weak 
snow near the ground. The severely injured rider had to be rope hauled back up the steep slope in a 
heroic late night rescue effort by Cache, Franklin, and Bear Lake County SAR. The east face of 
Logan Peak apparently also avalanched wall to wall and to the ground in the afternoon of 1-11-2014, 
and we're still unsure of the trigger. Observers noticed a couple natural persistent slab avalanches, 
which occurred in the afternoon yesterday 1-12-2014 at lower elevations in Logan Canyon...

Avalanche Problem 1

Very dangerous human triggered avalanches failing in old weak faceted snow or in the basal layers of 
the existing snow pack are still likely on steep drifted slopes today. You could trigger large and 
destructive avalanches remotely, from a distance, or worse, from below. Heavy snowfall and sustained 
strong west winds built significant cohesive and heavy slab on very weak sugary or faceted snow. This 
unstable snow structure is now widespread across the Logan Zone at all elevations.

Avalanche Problem 2

Here are are few reasons why you should avoid travel in avalanche terrain today:

1. Large avalanches occurred in the Logan Zone over the weekend, and some naturals were reported 
   from yesterday.

2. Observed audible collapsing or whoompfing. (observers report extensive collapsing in the 
   Garden City Canyon Area Sunday)

?3. Shooting cracks observed, some quite deep and long. 

4. Serious and significant drifting with sustained and strong west winds for the last 4 days.

5. Heavy snow and rapid overnight accumulations. 4.5" of water equivalent at Tony Grove 
   since 1-8-2014

Wind slab, storm snow, persistent slab, and deep slab avalanches are all likely in the backcountry 
today. Natural persistent slab activity reported at lower elevations yesterday.

Snow showers will probably continue for a while this morning, with another 1 to 3 inches of 
accumulation forecast and continuing fairly strong northwest winds. High temperatures at 8500' 
are expected to be around 28 degrees today, dropping to into the mid teens overnight. The stormy 
weather will move off to the east today and a strong high pressure system will gradually build 
over the region. Expect fair and sunny weather in the mountains tomorrow and for most of the 
coming work week.