Valdez

Forecast Expired

Above 3,000ftConsiderable

1,500 to 3,000ftModerate

Below 1,500ftLow

Degrees of Avalanche Danger

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Avalanche Problems

Problem 1

Wind Slab:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Storm Snow:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 3

Persistent Slab:

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

 Public observers witnessed natural avalanches on the Valdez Glacier Lake, Hogsback  Ridge and wet slide avalanche activity in the ice climbing areas of Keystone Canyon, Sheep Creek, Bear Creek, and Mineral Creek.  

  The avalanche near Valdez Glacier Lake was a Glide Crack release off a 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 XC ski trail.

Weather

   The strong front that traversed the area yesterday and brought warm temps and strong to moderate SE winds, is slowly exiting the area this morning.  Expect winds to become calm Tuesday,  precipitation to slowly taper off, and temperatures to fall slightly.  

  Skies will be clearing towards the evening hours before the next low pressure system meanders its way into the Gulf on Wednesday.  This low looks to be the weather maker for the remainder of the week.  There is low confidence in what the effects will be of this next system.

 

 

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`      39 F         29 F

Temp at 3000`      33 F         33 F

Chance of precip   90%          30%

Precip amount
(above 1000 FT)    0.19 in      0.02 in

Snow amount
(above 1000 FT)    0 in         trace

Snow level         2200 ft      sea level

Wind 3000` ridges  NE 2-10 mph  E 3-13 mph

Remarks...None.

  24h snowfall (inches) HN24W (inches)* Hi Temp (F) Low Temp (F) Dec snowfall Season Snowfall
Valdez 0 .78 41 32 7 31
46 mile 0 .25 43 32 ? ?

Nicks snotel

(4500′)

10 ? 34 30 ? ?
* HN24W= total water received last 24 hours in inches

Additional Information

 As of Tuesday morning, we have received 10″ of new snow in the last 24 hours at the Nick’s snotel at 4500′.  This snow was accompanied by moderate to strong SE winds which continued to build windslab on lee aspects.  Rain line likely went up to 4000 feet yesterday before dropping back down overnight.

 Human triggered avalanches are likely today in the upper elevations.  Avoid wind loaded slopes above 32°.  Windslab will often have a hollow, drum-like feel.  Also watch out for cornices that have likely grown in size over the last few days and will be adjusting to their new weight.

 In moderate elevations where rain fell on snow,  expect the hazard to decrease as temperatures cool.  Finding a rain crust on the surface will be a good indicator that the snow surface has refrozen and is beginning to gain strength.

 The avalanche hazard is low at low elevations due to lack of snow.  With that said it is still VERY important to keep clear from the lower elevation runout zones of large avalanche paths.  There has been a report of a Glide avalanche running all the way to the Valdez glacier lake on 12/9.

The hazard will SLOWLY decrease as temperatures cool off.  The snowpack will need time to adjust to its new load.  Be patient, and avoid cross-loaded gullies, avalanche paths, and terrain traps.  Careful decision making and route finding will be necessary.  

Forecast Confidence is low.

Announcements

The avalanche hazard is Considerable today at Upper elevations.  Triggering wind slab avalanches up to 2 1/2 feet deep will be likely today on NE through NW aspects, especially on the lee side of ridge lines.  Avoid travel in avalanche paths today and stay away from runout zones.  The danger will remain elevated until temperatures begin to fall and snowpack has time to except the new snowfall.