Avalanche Advisory
Advisory: Ogden Area Mountains Issued by Mark Staples for Wednesday - January 18, 2017 - 7:18am
bottom line

The avalanche danger is LOW on all aspects and elevations, and today is a great one to be in the mountains with warm temperatures and light winds. Avalanche conditions are generally safe, but avalanches are possible in isolated areas.
special announcement

Read a great new blog post by forecaster Drew Hardesty - Shame and the Social Contract
current conditions

This morning temperatures are warmer the higher you go. Temperatures are in the low teens F at low elevations and in the mid to high 20's F above 8000 feet. With an approaching storm winds shifted to the W overnight and increased at ridgetops blowing 15-20 mph. Below ridgetops, winds are blowing 2-5 mph.

On sunny aspects the snow surface has become wet each day and refrozen each night. On shaded aspects, the snow surface has remained dry but has weakened significantly. It contains a mix of small faceted crystals and surface hoar crystals which create "loud powder". Observers have noted these conditions throughout the Wasatch Range, and Craig Gordon found similar snow surface conditions yesterday in the Uinta Mountains. Watch his video below.
recent activity

With people enjoying beautiful weather and generally safe avalanche conditions, they have been riding slopes throughout the Wasatch Range. A group of skiers in the Central Wasatch Range triggered a few wind slabs that formed 2-3 days ago. Low danger doesn't mean No danger. These seem to be mostly isolated problems and easy to identify and manage. Photo below of a wind slab that broke 7 inches deep and 60 feet wide at 11,000 feet in Hogum Fork on a S aspect (recent winds were from the N).
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

A layer of weak facets exists above and below a thick rain crust from mid-December. This layer exist below 7500 feet and produced massive avalanches last week when it was stressed by heavy snowfall. Triggering an avalanche on this layer should be hard to do today, but it's worth digging into the snow 3-4 feet to look for and assess this layer.
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

Wind slabs formed 2-3 days ago from N winds. S and SW winds may form shallow wind slabs today. Look for these wind slabs under ridges or cross loaded gullies. They have a smoother and rounder appearance than other snow. Don't take anything for granted if riding in very steep or exposed terrain where the consequences of a very small slide can be deadly. I often try to find a way to ride around obvious wind slabs and avoid the problem altogether.

Watch for a few other avalanche problems including:

  • Huge cornices that can break and trigger avalanches or be a problem by themselves
  • Dry snow sluffs which are only a problem in very steep, extreme terrain
  • Wet loose avalanches - these occur on sunny slopes as the snow surface gets wet and are generally predictable both in where (sunny slopes) and when they occur (watch for small pinwheels of snow or other point releases as the day warms).
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

The snow surface today could become a weak layer in the future. Warm sunny days and clear cold nights weaken the snow surface and form surface hoar (a fancy name for frost that forms on the snow). Ways to spot these facets and surface hoar are:

  1. A sparkling snow surface.
  2. Slippery skin tracks.
  3. Powder snow that remains soft for long periods since the last storm.
  4. Soft snow that makes more noise compared to fresh powder.

Will it be a problem in the future? It's hard to say and highly dependent on the weather. This potential weak layer is easily destroyed by strong sunshine and/or strong winds. If the next storm arrives with light winds, this weak snow can be preserved and capped by new snow. If that happens, it will become a problem once a slab forms on top. Watch the video below of this weak surface snow from B. Smith near Ogden.
weather

Despite some approaching clouds in Nevada this morning, skies will be mostly sunny today. Temperatures will climb into the upper 30's F. Winds may increase some and blow 15 mph from the W by later today. A series of small storms will arrive on Thursday. None should bring significant snow; however, 5-10 inches is possible over the entire storm period of 4-5 days.

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 exist.