Valdez

Forecast Expired

Above 4,000ftHigh

2,000 to 4,000ftHigh

Below 2,000ftConsiderable

Degrees of Avalanche Danger

Avalanche Problems

Problem 1

Storm Snow:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Persistent Slab:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 3

Wind Slab:

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

12/31 Numerous small-medium natural avalanches observed below 4000′ on steep rollovers on the north side of the pass.

12/30  Natural avalanche observed on Cracked Ice Butress at 2700′.  300 meters wide~, 1 meter+ deep~.  Connected through gullies and over ridges.

D3 avalanche on east face of Mt. Tiekel mp 50 ran into top 1/3 of apron..

12/28- Several natural avalanches reported in the 54 mile area near brush line.  100′ wide and ran 300′.  Depth was not observed.

12/26- Skier triggered avalanche on Cracked Ice Buttress: N aspect, 2500′, 37° slope, 18 inches deep, 100 feet wide, ran 200-300 feet. SS-ASu-D1-R1-I

12/24- Skier triggered avalanche on Python Buttress: NW aspect, 2700′, 35° slope, 60 feet wide, ran 200-300 feet.  SS-ASu-D1.5-R1-O

12/18- A large glide release was reported off Snowslide Gulch middle peak size 2.5.

12/15- Observed small natural avalanche on west aspect of Goodwills.   Released below a cliff band at the bottom of a slope, 100′ wide.   SS-N-D1-N

12/8-  An observer witnessed a glide crack avalanche.  SW aspect of peak 4690′ above the Valdez Glacier Lake. The debris reportedly ran all the way to the lake, with the deposition pile only feet away from a well used cross country ski trail.

Weather

01/01- Snowfall will taper today and temperatures will fall. Winds are forecasted to be light from the south switching to north this evening.

The Thompson Pass Mountain Forecast covers the mountains (above
1000 ft) surrounding Keystone Canyon through Thompson Pass to
Worthington Glacier.

This forecast is for use in snow safety activities and emergency
management.

                   Today        Tonight

Temp at 1000`      29 F         14 F

Temp at 3000`      13-21 F      6-12 F

Chance of precip   80%          60%

Precip amount
(above 1000 FT)    0.11 in      0.04 in

Snow amount
(above 1000 FT)    1-2 in       0 in

Snow level         sea level    sea level

Wind 3000` ridges  SW 4-11 mph  NE 2-7 mph
 
  24h snowfall (inches) HN24W (inches)* Hi Temp (F) Low Temp (F) January snowfall Season Snowfall Snow height 
Valdez 2.5 1.15 33 28 2.5 73 32
46 mile 2 .4 37 28 12

Nicks Snotel “4500′”

11 30 21 139

 HN24W= total water received last 24 hours in inches

Additional Information

We have the perfect recipe for avalanches: a bed surface, a weak layer, and a slab.  The 12/9 rain crust will act as our bed surface.  Above the rain crust is our weak layer, a 5 cm layer of facets that has been created by the recent cold weather. Third is our slab, which has been created by snowfall that started 12/22, storm totals 110″ at Thompson Pass.  Human triggered and natural avalanches that happen within the upper snowpack could step down into lower layers and create very large avalanches.  Hazard will slowly decrease as temperatures fall and the snowpack is given time to accept its new load

 There have been limited observations from interior locations due to low snow at lower elevations.   Use caution if you travel in these areas.

If you have traveled in the mountains, please leave a public observation.  The more info we can get from various locations will help us to get a clearer picture of the snowpack in our beautiful Valdez Chugach! 

Forecast Confidence is Moderate.

Video taken 12/20 in the Mt. Dimond area showing reactive test slopes.   https://vimeo.com/user106668057/review/380916811/02da5d1cc7

Alerts

Happy New Year!!! The avalanche hazard is High at mid and upper elevations on all aspects.   Human triggered avalanches are very likely today.  Thompson Pass has received impressive snowfall starting 12/22 with totals approaching 10 feet. We are still within 24 hours of significant snowfall, the snowpack will need time to adjust.   Avoid travel in avalanche terrain today.  Stay clear of avalanche runout zones.  The hazard will slowly decrease as temperatures fall and snowfall stops.