Thursday-Sunday 3/29-4/1

Issued: Thu, Mar 29, 2018 at 8AM

Expires: Sun, Apr 01, 2018

Bring your families and kids out to Beacons & Eggs. Saturday March 31 10am-noon. Salmon Berry Ski Hill at Mile 6. Learn and practice backcountry safety skills with some Easter fun!

Above 2,500ft Low

1,800 to 2,500ft Low

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

Thursday Friday Saturday & Sunday
1-low 1-low 2-moderate



Elevation:   Above 4000′
Aspect:   Lee of ridges, gullies, ridgetops
Terrain:   Northerly facing terrain above 35< and exposed to winds
Sensitivity:   Stubborn
Distribution:   Specific
Likelihood (Human Triggered):   Possible
Size:   Small 
Danger Trend:   Steady
Forecaster Confidence:    Fair

Sensitivity: Non-reactive, Stubborn, Responsive, Touchy
Distribution: Isolated, Specific, Widespread
Likelihood: Unlikely, Possible, Likely, Nearly Certain
Size: Small, Large, Very Large (size scale <here>)
Danger Trend: Increasing, Steady, Decreasing
Forecaster Confidence: Good, Fair, Poor


SNOWPACK DISCUSSION:     The advisory area experienced a significant wind event March 19-22.  These northerly winds scoured loose snow leaving a pencil hard wind layer on the surface. Gullies were filled in with deep, smooth wind slab and snow surface textures vary from sastrugi to patches of softer wind and sun effected snow.  Since the wind event, the temperatures have remained mostly below or near freezing.  The wind slabs have been settling and creating stronger bonds.

Test pits over the last week have shown no signs of propagation.

The relatively warm daytime temperatures and consistent solar radiation is causing southerly aspects to thaw.  Rapid thawing can quickly change the stability of the snowpack and lead to avalanches.  If you see or experience signs of rapid warming such as: temperatures above freezing, roller balls or pinwheels in the snow, wet avalanches, or heavy/sticky snowpack, it’s time to get out of avalanche terrain.

Check out our public observations <here>


Recent Avalanche Activity

March 22: A few pockets of windslab released on steep west facing gully walls and rollovers including a D2 wind slab on S facing slope at 3500′ near milepost 29.

Video of Winds from 3/22/18

March 21: Natural wind slabs to size D2, including onto the highway at Milepost 23.
March 19-20: Numerous natural wind slab releases to size D2 observed between Mileposts 22 and 29 across Thompson Pass with the initial onset of the present extreme northerly wind event, transporting available soft snow.


Recent Weather

WEATHER FORECAST for NEXT 24 HRS at 3,000 ft:
Temperature Forecast (Min/Max *F): 13 / 23
Ridgetop Wind Forecast (direction/mph): NE / 3-20
Snowfall (in):  0”
PAST 24 hours
Ferry Terminal Thompson Pass
Average Wind Speed (mph) / Direction  3 / NNE   14 / NE
Max Wind Gust (mph) / Direction  6 / NNE  21 / NE
Temperature Min / Max (*F)  20 / 40  17 / 26

Weather Forecast:   Mostly sunny with light winds. In the alpine, temperatures will most likely stay below freezing during the day and around 15*F (-9*C) in the evening.  Lower elevation temperatures will likely rise above freezing during the day and drop below freezing at night.  No snow in the forecast.

Additional Info & Media

SNOW HISTORY: Valdez 3/29 AM Thompson Pass 3/29 AM
24 Hour Snow / Water Equiv. 0”/ 0.0″ 0″ / 0.0″
Storm Snow /Water Equiv. (3/15-19) 19” / 0.41″ 40″ / 1.5″
Current Snow Depth 32″ 60″
March Snow / Water Equiv. 20.5″ / 2.61″ 49″ / 3.6″
Total Winter Snowfall / Water Equiv. 132.59″ / 27.2” 372″ / 36.6″
Snowload in Valdez 45 lbs/sq. ft.


SNOW DEPTH & WATER SURVEY (3/4/2018) Depth Snow Water Equivalent
Milepost 2.5 Valdez  32.2″  9″
Milepost 18 42″ 11″
Milepost 29 Worthington Flats 62.4″ 21.2″
Milepost 37 Tsaina River bridge 58.4″ 14.2″
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.

Forecaster: Ryan Van Luit