December 25, 2017 Christmas Day

Issued: Mon, Dec 25, 2017 at 8AM

Expires: Thu, Dec 28, 2017

Merry Christmas from our Valdez Avalanche Center staff and volunteers!
To avoid triggering a windslab avalanche avoid steep slopes loaded by the north wind – especially rocky gullies just off upper ridgelines.


Above 2,500ft Moderate

1,800 to 2,500ft Moderate

Below 1,800ft Low

Degrees of Avalanche Danger ?

1. Low
2. Moderate
3. Considerable
4. High
5. Extreme

Avalanche Danger Rose ?

Avalanche Problems ?

Problem Details

The last snowfall, Dec.19, delivered 10″(25cm) to Thompson Pass and 13″(33cm) in Valdez. The new snow is settling and bonding to surfaces below. Since the snowfall ended, light to moderate north wind above treeline has pressed and drifted it into pockets of soft windslab.

Yesterday, a tour above 35 Mile found no signs of significant instability. An air temperature inversion of -20F in creek bottom to +20F above 3000′ was measured.

Above treeline, surfaces are variable due to wind stripping down to the old Dec.18 crust in places. Depths of new snow and overall snowpack, increase with elevation. In one test pit dug (12/22) at 4600′ on a south aspect, the interface of the new and old snow was found 30″ (76cm) from the surface and was unreactive.


Recent Avalanche Activity

No recent avalanche activity reported or observed. Last activity was from Dec.19; a few pockets of windslab to size 2 released out of steep, rocky features, mostly southerly aspects above 4500′, triggered by north windloading.

Recent Weather

WEATHER FORECAST for NEXT 24 HRS at 3,000 ft:
Temperature Forecast (Min/Max *F):   9/22
Ridgetop Wind Forecast (direction/mph):  NE/1-13
Snowfall (in/water equivalent): 1″ /0.03″
PAST 24 hours
Ferry Terminal Thompson Pass
Average Wind Speed (mph) / Direction   light/variable 12 /NE-SE
Max Wind Gust (mph) / Direction   6 /NNE  19/NE
Temperature Min / Max (*F) 22 /28 8/25

Weather Forecast:

Mostly cloudy with a chance of flurries. Clearing trend into tomorrow morning. Light to moderate northeast wind. Temps warming slightly with a trace to inch of snow.

Additional Info & Media


SNOW HISTORY: Valdez 12/24 AM Thompson Pass 12/24 AM
24 Hour Snow / Water Equiv. 0”/ 0″ 0″ /0″
Storm Snow /Water Equiv. [12/19]  13″/0.88″ 10″ /1″
Current Snow Depth 16″ 60″
December Snow / Water Equiv. 38″ /13.17″ 132″ / 17.6″
Total Winter Snowfall / Water Equiv. 51″ /15.42” 197″ / 23.1″
Snowload in Valdez 42 lbs/sq. ft.


Nicks Valley at 4200 ft (in): 0″ / 10″ /?”
Upper Tsaina at 1750 ft (in): 0″ / 8″ /?”
Sugarloaf at 550 ft (in): 0″/ 12″ /1″
SNOW DEPTH & WATER SURVEY (12/2017) Depth Snow Water Equivalent
Milepost 2.5 Valdez  ″  ″
Milepost 18
Milepost 29 Worthington Flats
Milepost 37 Tsaina River bridge
This survey is done the first week of each month.

Weather Quicklinks:


  • coastal-zone-iconMaritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
  • intermountain-zone-iconInter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
  • interior-zone-iconContinental (Interior) – the dry north side of the Chugach (north of 46 Mile, including the Tonsina River).

Photo of Thompson Pass


Interactive Map of Valdez Forecast Areas w/ Many Resource Layers (Trevor Grams)


Run Map of Thompson Pass Area (Sean Wisner) (2MB download)
VAC Run Map Thompson Pass

NEWS: Our region is “one of the snowiest places on earth” – Serendipity / Rendezvous snowfall record set in 1963 <here>.

Free smart phone avalanche forecasts at:

Posted in Continental Forecasts, Intermountain Forecasts, Maritime Forecasts, VAC Forecasts.

Forecaster: Ryan Van Luit