Valdez

Forecast Expired

Above 4,000ftConsiderable

2,000 to 4,000ftConsiderable

Below 2,000ftLow

Degrees of Avalanche Danger

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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

Deep 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

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`      19 F         3 F

Temp at 3000`      4 to -10 F   8 F

Chance of precip   80%          50%

Precip amount
(above 1000 FT)    0.06 in      0.03 in

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

Snow level         sea level    sea level

Wind 3000` ridges  E 3-16 mph   NE 4-14 mph

Remarks...Increasing NE flow will develop late Fri. These winds
combined with falling temperatures could make for wind chills
near -40 F
 
  24h snowfall (inches) HN24W (inches)* Hi Temp (F) Low Temp (F) January snowfall Season Snowfall Snow height 
Valdez         2.5 73 32
46 mile trace 0 28 14 12

Nicks Snotel “4500′”

0 31 7 135

 HN24W= total water received last 24 hours in inches

Additional Information

We are on the tail end of a major series of storms.  The new snow has opened up different access points.  Use caution as you step forward into new zones.  New snow combined with strong winds from different directions has created a lot of spatial variability in our area.  Careful snowpack evaluation and conservative terrain choices will be critical today.  The hazard will slowly decrease with time.

Below 4000′ the new snow is sitting upon a layer of facets, and will have the potential of creating large avalanches .  

 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

Announcements

The avalanche hazard is considerable at mid and upper elevations.  Human triggered avalanches are likely.  Thompson pass has received 10 feet of snow since 12/22 combined with strong winds.     The snowpack will need time to adjust to this new snow.  Avoid large avalanche paths, steep slopes and terrain traps.