Avalanche Advisory
Advisory: Logan Area Mountains Issued by Toby Weed for Sunday - December 24, 2017 - 7:08am
bottom line

Dangerous avalanche conditions exist in the backcountry and human triggered avalanches are likely. Another round of stormy weather tonight could cause the danger to increase further for Christmas, and you should plan to avoid travel in avalanche terrain.

  • Evaluate the snow and terrain carefully, make conservative decisions, and avoid steep drifted slopes.



avalanche watch

THE FOREST SERVICE UTAH AVALANCHE CENTER IN SALT LAKE CITY HAS ISSUED A BACKCOUNTRY AVALANCHE WATCH.

* TIMING...FROM 0600 MST THIS MORNING UNTIL 0600 MST MONDAY MORNING

* AFFECTED AREA...FOR THE MOUNTAINS OF NORTHERN UTAH INCLUDING THE WASATCH RANGE, OGDEN AREA MOUNTAINS, BEAR RIVER RANGE, AND THE WESTERN UINTAS.

* AVALANCHE DANGER...THE AVALANCHE DANGER FOR THESE AREAS WILL BE RISING AND COULD REACH HIGH WITHIN THE NEXT 24 HRS. SNOWFALL TONIGHT WILL POTENTIALLY MAKE VERY DANGEROUS AVALANCHE CONDITIONS.

* REASON/IMPACTS...ADDITIONAL HEAVY SNOW COMBINED WITH WIND COULD CREATE WIDESPREAD AREAS OF UNSTABLE SNOW. BOTH HUMAN TRIGGERED AND NATURAL AVALANCHES WILL BECOME LIKELY. STAY OFF OF AND OUT FROM UNDER SLOPES STEEPER THAN 30 DEGREES.

BACKCOUNTRY TRAVELERS SHOULD CONSULT WWW.UTAHAVALANCHECENTER.ORG OR CALL 1-888-999-4019 FOR MORE DETAILED INFORMATION.

THIS WATCH DOES NOT APPLY TO SKI AREAS WHERE AVALANCHE HAZARD REDUCTION MEASURES ARE PERFORMED.
current conditions

Dangerous avalanche conditions exist in the backcountry. The Tony Grove Snotel at 8400' reports 17 inches of new snow yesterday, with 2.0" SWE (Snow Water Equivalent). It's 8°F at the site and there's 44" of total snow containing 98% of average SWE. It's 2°F at the 9700' CSI Logan Peak weather station, and the wind sensor is rimed or encased by ice and not reading. Northwest wind speeds diminished into the single digits overnight at the UDOT Hwy 89 Summit weather station.

  • There is more total snow and better coverage in the central and northern Bear River Range and at upper elevations.
  • 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.
recent activity


We received reports of numerous natural, easily triggered, and remote triggered soft slab avalanches in the Logan Zone yesterday.
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

Across the Logan Zone, wind slabs are forming on weak preexisting snow. Dangerous wind slab avalanche conditions exist in exposed terrain at upper and mid elevations. The danger could rise further tonight as the next wave of Pacific storminess impacts the area, with more snow and drifting from strong west winds. Human triggered wind slab avalanches are likely on drifted slopes.

  • Wind slabs, consisting of stiffer, drifted snow may be chalky in appearance and might produce hollow sounds.
  • Avoid fresh drifts in steep terrain near ridges and in and around terrain features like gullies, saddles, rock bands, scoops, and sub-ridges.
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

As the fresh Christmas snow stacks up on slopes plagued by very weak sugary or faceted snow, storm snow avalanches are likely even in sheltered areas.

  • Pay attention to possible signs of instability like cracking and whumpfing or collapsing.
  • Avalanches might be triggered remotely, from a distance, or worse, from below.
  • Sluffs or avalanches entraining loose snow are possible in steep terrain.
  • A ride in even a small avalanche could be particularly dangerous now due to hard underlying snow and real potential for being dragged through rocks or deadfall below.
weather

A weather system will cross mainly northern portions of the region tonight into Monday, while the south remains dry. A generally dry northwest flow will follow for Monday night and Tuesday.

  • Snow is possible this afternoon. Expect increasing cloudiness, with a high temperature at 8500' around 24°F and 9 to 14 mph west winds, veering from the southwest in the morning. Wind chill values will be as low as -10°F.
  • It will snow tonight, with 4 to 8 inches possible. Low temperatures are expected to be around 24°F, with 15 to 20 mph west-southwest wind.
  • Snow will continue into Christmas Day, with 3 to 5 inches possible. Temperatures will drop to around 22°F, and west winds will blow 20 to 22 mph.
general announcements

Don’t know what to buy your favorite skier for Christmas? Discount lift tickets for Alta, Snowbird, Brighton, Solitude, Deer Valley, Snowbasin, and Beaver Mountain are now available, donated by the resorts to benefit the Utah Avalanche Center. Details and order information here. These make a great holiday gift and all proceeds go towards paying for avalanche forecasting and education!

Now is a great time to practice companion rescue techniques with your backcountry partners. Here's our rescue practice video.

Go HERE for a list of UAC classes.

EMAIL ADVISORY: If you would like to get the daily advisory by email you will need to subscribe here.

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 observations. 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.