Avalanche Advisory
Advisory: Salt Lake Area Mountains Issued by Mark Staples for Monday - February 27, 2017 - 6:28am
bottom line

With plentiful new snow and strong SW winds, the avalanche danger this morning is CONSIDERABLE mainly for wind slab avalanches at mid and upper elevations. As the new snow rapidly accumulates, storm slab avalanches may be triggered even on wind sheltered slopes. Some naturally occurring avalanches will be possible later this morning with intense snowfall and continued strong winds.




current conditions

Its snowing this morning over an inch per hour with about 6 inches in most places as of 6 a.m. Upper Big Cottonwood Canyon is favored during a SW flow and had 8.5 inches of snow as of 6 a.m.

Winds increased from the SW yesterday afternoon and were averaging 20 mph with gusts of 30-60 mph this morning. These winds will easily drift and transport the new snow as well as snow that fell from the last storm. Temperatures increased since yesterday and are mostly in the upper teens F above 8000 feet.

Photo below of winds that were already transporting snow and growing corninces yesterday afternoon (M. White)

Also - a few people noted some radiation recrystallized facets forming on the snow surface yesterday. Sunshine warms the snow a inch or two deep while the snow surface remains very cold. As the warm snow refreezes overnight, it forms a fragile ice crust with a thin layer of small, weak faceted crystals on top. These small facets shouldn't be a long lasting problem but should make wind slabs and storm snow avalanches easier to trigger today. Look for the thin ice crust as an indication that these small facets exist.

recent activity

The only avalanches reported yesterday were a few wind slabs triggered by explosives in Little Cottonwood Canyon.

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

Strong SW winds and potentially heavy snowfall will form fresh wind slabs that will be easy to trigger today. If strong winds continue, some wind slabs could release naturally in the middle of the day. If winds ease today, continued snowfall will mask these winds slabs and make them harder to spot. Today will be a good one to ride great powder at lower elevations in terran sheltered from the wind.

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

Today as new snow rapidly accumulates, avalanches could begin occurring even in non-wind affected terrain. Sluffing in the new snow will be a warning sign of a rising danger telling us that the new snow is not bonding well to itself or the old snow underneath it. Cracking in the new snow will tell you that a slab is beginning to form and storm slab avalanches could be triggered. If you find a fragile ice crust and small facets buried under the new snow (see note in Current Conditions), this avalanche problem will be even more sensitive.

Avalanche Problem 3
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 24 hours
description

It's hard to predict when or where cornices will break. However, there are two things we know: They will be growing today with new snow and strong SW winds which will add more weight, thus adding more stress and making them more likely to break. We also know where they exist and can avoid being under or on top of them.

weather

Snowfall will continue most of today with the heaviest snowfall ending this afternoon. Temperatures shouldn't warm as cold air enters the area and prevents day time warming. By the end of today, storm totals could easily be 1.5 feet of new snow or more. Upper Big Cottonwood Canyon was halfway to that total as of 6 a.m. Winds should slowly ease some, and blow 10-20 mph from the SW with gusts of 30 mph but remain strong enough to easily transport the new snow.

general announcements

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.

To get help in an emergency (to request a rescue) in the Wasatch, call 911.  Be prepared to give your GPS coordinates or the run name. Dispatchers have a copy of the Wasatch Backcountry Ski map.

Backcountry Emergencies. It outlines your step-by-step method in the event of a winter backcountry incident.

If you trigger an avalanche in the backcountry, but no one is hurt and you do not need assistance, please notify the nearest ski area dispatch to avoid a needless response by rescue teams. Thanks.

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

DAWN PATROL Hotline updated daily by 5-530am - 888-999-4019 option 8.

TWITTER Updates for your mobile phone - DETAILS

UDOT canyon closures:  LINK TO UDOT, or on Twitter, follow @UDOTavy, @CanyonAlerts or @AltaCentral

Utah Avalanche Center mobile app - Get your advisory on your iPhone along with great navigation and rescue tools.

Powderbird Helicopter Skiing - Blog/itinerary for the day  

Lost or Found something in the backcountry? - http://nolofo.com/

Ski Utah mobile snow updates

To those skinning uphill at resorts:  it is critical to know the resort policy on uphill travel.  You can see the uphill travel policy for each resort 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.

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.