• Backcountry Avalanche Forecast
  • Forecast Discussion
  • Observations & Weather Data

Tue, Jan 15, 2019 at 7:17 AM
Issued by: Brian Lazar

Today

 

Tomorrow

Moderate (2) Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully.   Moderate (2) Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully.
Moderate (2) Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully.   Moderate (2) Heightened avalanche conditions on specific terrain features. Evaluate snow and terrain carefully.
Low (1) Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.   Low (1) Generally safe avalanche conditions. Watch for unstable snow on isolated terrain features.
  Danger Scale

  • No Rating
  • 1
    Low
  • 2
    Moderate
  • 3
    Considerable
  • 4
    High
  • 5
    Extreme

Summary

Recent avalanches, including a remotely-triggered slab  in the Gore Range and a likely close call near Georgia Pass, provides clear evidence that you can trigger a dangerous avalanche if you find a stiff slabs resting on buried weak layers. You're most likely to find this combination on north and east-facing slopes at higher elevations. Older slabs of dense wind-drifted snow are becoming hard to trigger, but the resulting avalanches will be large and difficult to escape. You are more likely to trigger avalanches from the margins of slopes, around steep rollovers, or over rock bands where the weak layers are closer to the surface making them easier to affect. 

Sheltered terrain at lower elevations offers safer options, but you still need to keep an eye out for signs of instability such as cracking and collapsing before you venture into steeper terrain. Avoid riding on slopes with terrain traps below you. We had a few close calls in other zones over the past few days and at least one rider was caught and buried in an avalanche because the snow washed them into the trees. 

 

Avalanche Problem

 
problem icon
N
S
E
W
NW
NE
SE
SW
Above Treeline
Near Treeline
Below Treeline
Certain
Very Likely
Likely
Possible
Unlikely
Historic
Very Large
Large
Small
Avalanche Character Aspect/Elevation Likelihood Size

What You Need to Know About These Avalanches


Persistent Slab avalanches can be triggered days to weeks after the last storm. They often propagate across and beyond terrain features that would otherwise confine Wind and Storm Slab avalanches. In some cases they can be triggered remotely, from low-angle terrain or adjacent slopes. Give yourself a wide safety buffer to address the uncertainty.

Avalanche Problem

 
problem icon
N
S
E
W
NW
NE
SE
SW
Above Treeline
Near Treeline
Below Treeline
Certain
Very Likely
Likely
Possible
Unlikely
Historic
Very Large
Large
Small
Avalanche Character Aspect/Elevation Likelihood Size

What You Need to Know About These Avalanches


Storm Slab avalanches release naturally during snow storms and can be triggered for a few days after a storm. They often release at or below the trigger point. They exist throughout the terrain. Avoid them by waiting for the storm snow to stabilize.

Avalanche Problem

 
problem icon
N
S
E
W
NW
NE
SE
SW
Above Treeline
Near Treeline
Below Treeline
Certain
Very Likely
Likely
Possible
Unlikely
Historic
Very Large
Large
Small
Avalanche Character Aspect/Elevation Likelihood Size

What You Need to Know About These Avalanches


Deep Persistent Slab avalanches are destructive and deadly events that can release months after the weak layer was buried. They are scarce compared to Storm or Wind Slab avalanches. Their cycles include fewer avalanches and occur over a larger region. You can triggered them from well down in the avalanche path, and after dozens of tracks have crossed the slope. Avoid the terrain identified in the forecast and give yourself a wide safety buffer to address the uncertainty.

Weather Forecast for 11,000ft Issued Tue, Jan 15, 2019 at 11:28 AM by Brian Lazar Statewide Weather Forecast
  Tuesday Night Wednesday Wednesday Night
Temperature (ºF) 15 to 20 25 to 30 12 to 17
Wind Speed (mph) 5 to 15 12-22 G30 15-25 G30
Wind Direction SW W W
Sky Cover Mostly Cloudy Mostly Cloudy Mostly Cloudy
Snow (in) 0 to 1 1-3E, 3-5W 0 to 2

Archived Forecasts

  • Select Forecast: Valid

Tue, Jan 15, 2019 at 7:54 AM
Issued by: Brian Lazar Statewide Weather Forecast  

This incoming winter storm will increase the hazard in the Steamboat-Flat Top zone by tomorrow if the forecast verifies. Expect avalanches in the accumulating storm snow to be a threat by tomorrow. Other areas of the Northern Mountains will see less snowfall out of this storm, but the snowpack is weak out side the Steamboat area and Park Range.  Small amounts if incremental loading from new and drifting snow will make avalanchew slightly easier to trigger over the next day or two. A bigger thump Thursday night and into Friday should be enough to increase the hazard across most of the Northern Mountains. 

Here is a partial list of the recent avalanche activity over the last week throughout the Northern Mountains: Flat Tops - Snowmobile triggered slid in the southern Flat Tops. Front Range -  Mt Trelease, Current Creek, Sheep Creek. Vail/Summit County - Mt Royal, Mt Lincoln, Mt Guyot, a near miss on Georgia Pass, Gore Range., Monteuma. I also wanted to highlight this one from the Sawatch as it occurred in a similar snowpack to  thinner and weaker areas that have received less snowfall this year. 

Pay attention to the slope characteristics of these avalanches. Avalanches triggered in the new snow were on steep slopes or rollovers. These avalanches were on the smaller side but could be dangerous if the slope you are on ends in a cliff or thick stand of trees. Many of the other avalanches failed as a result of recent loading, either by new snow or by wind-transported snow. These avalanches were much larger and in many cases broke into deeper weak layers. Slopes with dense slabs resting above persistent weak layers will continue to haunt us for the foreseeable future. Each new storm will reactivate these poor structures, so give extra caution to steep slopes during and following a storm cycle. 

The examples above show the dangerous results if you trigger an avalanche. Continue to use good backcountry travel protocols and default to lower angle terrain to avoid a run-in with a large and deadly avalanche.

 


  • The crown failed deeply into older weak layers near thin rocky spots (full)
  • Natural avalanche in the backcountry near Vail. Northeast-facing near treeline (full)

See more photos & videos

Five Day Trend

Saturday

Sunday

Monday

Today

Tomorrow

danger icon danger icon danger icon danger icon danger icon
danger icon danger icon danger icon danger icon danger icon
danger icon danger icon danger icon danger icon danger icon

  • No Rating
  • 1
    Low
  • 2
    Moderate
  • 3
    Considerable
  • 4
    High
  • 5
    Extreme
Avalanche Observations
Report Date # Elevation Aspect Type Trigger SizeR SizeD
View Sun Jan 13 - TL W SS AS / c R2 D2
View Sun Jan 13 - >TL E SS N R1 D1.5
View Sun Jan 13 - TL NE HS AS / u R2 D1.5

See All Avalanche Observations

Field Reports
Report Date Observer Snowpack Obs Avalanches Media
View Sun Jan 13 - No Yes (1) No
View Sun Jan 13 - No Yes (1) Yes (3)
View Sun Jan 13 Brian Binge No Yes (1) Yes (7)
View Sun Jan 13 - No Yes (1) Yes (2)

See All Field Reports

Weather Observations
Station Date Time Temperature Relative Humidity Wind Speed Wind Direction Max Gust 24 Hr Snow
A-basin Sa-summit Wed Jan 16 2:00 AM 18 87 15 193 27 -
Vail Pass - Cdot Yard Wed Jan 16 2:00 AM 22 89 1 143 4 0.4
Fremont Pass Wed Jan 16 2:00 AM 21 - - - - -
Grizzly Peak Wed Jan 16 1:00 AM 28 - - - - -
Hoosier Pass Wed Jan 16 1:00 AM 21 - 3 163 - -

See All Weather Observations