Avalanche Advisory
Advisory: Ogden Area Mountains Issued by Drew Hardesty for Monday - March 13, 2017 - 7:02am
bottom line

This morning's LOW danger will rapidly rise to at least MODERATE with direct sun and daytime highs reaching toward 50°F at 8500'. All elevation sunny aspects and low elevation northerly aspects will be most susceptible to natural and human-triggered wet activity. If and when the snow becomes wet and unsupportable, it's time to move to a cooler aspect or low angle slopes.




special announcement

Spring Special: We have a few donated Snowbird, Snowbasin, Solitude, and Brighton discount lift tickets left and have just lowered the price. Ski a day and benefit the Utah Avalanche Center! Order here.

SL Tribune reporter Erin Alberty had an "above the fold" front page article yesterday about the Birthday Chutes avalanche involvement from late December. It's a good read - Unlikely Survivors - What a Violent Avalanche Says About Risk in the Backcountry.
current conditions

Under the full moon, skies are clear as the snowpack radiates its heat out into the universe. Mountain temperatures are in the mid to upper 20s along the ridgelines, but the low and mid-elevation temps are in the mid to upper 30s. Winds are westerly, blowing 15, gusting to 30. All but the high due northerlies will host varying degrees of supportable to breakable melt-freeze crusts this morning. It's a good refreeze. That remaining piece of terrain - the high true north - holds chalky-to-decomposing wind damage. Still, travel is easy and views are 5-star.

recent activity

Some cloud cover, cooler air, and gusty winds held the wet activity at bay for as long as it could...which was until 4pm yesterday - at least in the central Wasatch. A sizable wet loose point release spilled out out one of the White Pine Chutes, a steep south facing couloir in Little Cottonwood Canyon. It's a sign of things to come.

Avalanche Problem 1
type aspect/elevation characteristics
LIKELIHOOD
LIKELY
UNLIKELY
SIZE
LARGE
SMALL
TREND
INCREASING DANGER
SAME
DECREASING DANGER
over the next 12 hours
description

Just like clockwork, today's sunny aspects will transition from rock-hard coral to soft, damp, and supportable to wet and unstable. Play your cards right in playing your aspects right. Move from east to south to west facing terrain to catch that "soft, damp and supportable window" on each. And timing is everything. Arrive too early and it's a visit to the dentist's office. Arrive too late and you've put yourself at risk for wet avalanches. If you're riding through unsupportable wet snow, seeing pinwheels and rollerballs, or observing natural wet loose sluffs, it's time to hit the road.

At some point over the next several days, we may start to see wet slab avalanches. It's possible today, but more likely over the next several days and perhaps into the weekend as we start to see radically warm temperatures during the day and superficial refreezes - at best - during the overnight hours. See a quick primer on wet slabs below (or YouTube link here).
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 cornices along the mid and upper elevation ridgelines have become enormous and unruly this year. With enhanced warming, they will continue to be exceptionally dangerous and unstable. Remember that they will break well back beyond the apex of the ridgeline. It's best to approach any ridgeline with caution or with a spotter who can see where the snow ends and the earth begins. These cornices have gained enough mass to potentially trigger an avalanche on the slope below. Cornice-fall and cornice-related avalanches account for roughly 5% of our avalanche fatalities. Glide avalaches just under 2%.
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

Glide avalanches are challenging to predict, but tend to release during periods of rapidly warming temperatures that both enhance the slow downhill glide rate of the entire snowpack and allow for snow melt to percolate down to the ground interface. They can release without warning anytime - day or night - and produce large, catastrophic avalanches and impressive debris piles. Glide releases are rare in the Ogden area mountains, but some have been noted north of Snowbasin and north of Ben Lomond. Click on the 'i' next the to info-graphic for more info.

weather

We'll have mostly sunny skies today with temps warming to near 50 at 8500' and near freezing along the ridgelines. Northwest winds will blow 15mph. Temps will continue to warm each day - reaching 40°F at ridgetop level by tomorrow afternoon/evening. A weak disturbance quickly moves through on Thursday, but this is only a pause as ridgetop temps spiral even toward the mid to upper 40s by the weekend.

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.