Valdez

Forecast Expired - 12/25/2019

Above 4,000ftModerate

2,000 to 4,000ftModerate

Below 2,000ftModerate

Degrees of Avalanche Danger

Avalanche Problems

Problem 1

Loose Snow:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Wind Slab:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 3

Glide Avalanches:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

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

12/24- Snow is forecasted for our region today with .6 inches of water expected over the next 24 hours.  This could produce 6-10 inches of additional new snow by tomorrow morning.

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`      27 F         23 F

Temp at 3000`      30 F         16-30 F

Chance of precip   90%          90%

Precip amount
(above 1000 FT)    0.40 in      0.20 in

Snow amount
(above 1000 FT)    4-8 in       2-4 in

Snow level         700 ft       sea level

Wind 3000` ridges  E 4-22 mph   S 10-23 mph
  24h snowfall (inches) HN24W (inches)* Hi Temp (F) Low Temp (F) Dec snowfall Season Snowfall Snow height 
Valdez 3 .19 27 23 14 38 18
46 mile 1 .15 5 -2 5

Nicks snotel

(4500′)

6 23 17 93

 HN24W= total water received last 24 hours in inches

Additional Information

Our area has received 6-12 inches of dry snow over the last 48 hours.  This new snow is sitting on a variety of wind affected snow surfaces ranging from pencil hard wind slab to areas that were stripped down to the 12/9 rain crust.  The new snow has been found to be very uncohesive so far, but where it was exposed to wind, expect slabs to be forming and to be sensitive to triggers.  Allow the snowpack time to properly bond with the new storm snow.  With an additional 6-12 inches forecasted for our area over the next 24 hours, watch for the hazard to increase to considerable, especially if we receive more snow than forecasted or winds are stronger than expected.

The further north you go from Thompson Pass, expect thinner snowpacks.  Triggering an avalanche on a persistent weak layer will be more likely in the continental zone.

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 Moderate at all elevations.  Human triggered avalanches are possible today on all aspects.  Our area has received 6-12 inches of new snow in the last 48 hours and is sitting on a variety of wind affected snow.  Look for the hazard to increase through the day as an additional 4-8 inches of snow is forecasted.  Shooting cracks and collapsing will indicate unstable snow.  Use caution in the mountains today, avoid steep slopes and terrain traps.