Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Monday - December 4, 2017 - 7:02am
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CONSIDERABLE: Dangerous avalanche conditions exist on upper elevation slopes in the backcountry. Human triggered storm snow and wind slab avalanches are likely. Avoid steep drifted slopes at upper elevations.

  • Fast moving and long-running avalanches are possible on smooth and very hard underlying snow.
  • Avalanches could be triggered remotely, from a distance or below.
special announcement

Please join us for our 14th annual "Pray for Snow" fundraiser/party, Thursday, December 7 at 6 PM. This year's new location is at the new Cache Venue, 119 South Main St in downtown Logan. Go HERE for advance tickets and more information.
current conditions

Looks like a powder day! Lots of nice light Utah snow fell overnight, and riding conditions will be excellent. But dangerous avalanche conditions likely exist on many steep upper elevation slopes. The Tony Grove Snotel at 8400' reports 27" of new snow containing 1.7" SWE (Snow Water Equivalent) and 14°F this morning. There's 45" of total snow containing 125% of average SWE. It's 7°F at 9700' at the CSI Logan Peak weather station, with diminishing west wind currently blowing 10 mph and gusting to 30 mph.

Just beneath the fresh powder, shallow early season snow conditions exist, and hitting rocks or stumps is a significant hazard. Travel cautiously and keep your speed down. The Tony Grove Road is not maintained for wheeled travel in the winter.

The snow surface at upper elevations Saturday was sparkling with widespread feathery surface hoar or frost crystals. Surface hoar often becomes a tricky persistent weak layer once buried. (Jensen, 12/2/17)
Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

Record warmth around Thanksgiving melted a good deal of snow across the zone, and a solid refreeze last week turned the remaining snow rock hard. A couple brush-by storms deposited an inch or two of snow and this is now weak. The fresh new snow may not bond well to the hard Thanksgiving snow surface especially on slopes where yesterday's surface snow is weak, faceted and in some areas capped with surface hoar of frost. It may become possible to trigger avalanches remotely or from a distance. Storm snow avalanches could be fairly wide and might run fast and far on the slick underlying snow. A ride in even a small avalanche could be particularly dangerous due to the hard underlying snow and potential for being raked through rocks or deadfall below.

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

The powder snow will easily be drifted into stiffer wind slabs in exposed terrain. Avoid fresh drifts near ridges and in and around terrain features like gullies, rock bands and sub-ridges.
weather

A cold Pacific storm system will slowly exit the area today. Strong high pressure aloft will cover the western states through the week. Snow showers will taper off this morning, then skies gradually become partly cloudy. High temperatures at 8500' will be around 17°F, with 15 to 20 mph northwest wind ​decreasing to 10 to 15 mph this afternoon. Tonight will be partly cloudy with a low around 9°F and 8 to 10 mph northwest wind. It'll be mostly sunny tomorrow with a high around 23°F and steady 9 mph northwest winds.

general announcements

We are offering a Backcountry 101 Avalanche Class on December 12 and 14 in the Logan Area Backcountry.

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Benefit the Utah Avalanche Center when you shop from Backcountry.com or REI: Click this link for Backcountry.com or this link to REI, shop, and they will donate a percent of your purchase price to the UAC. Both offer free shipping (with some conditions) so this costs you nothing!

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.

Remember your information can save lives. If you see anything we should know about, please help us out by submitting snow and avalanche conditions. You can also call us at 801-524-5304, email by clicking HERE, or include #utavy in your tweet or Instagram.

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.