Thursday-Sunday 3/9-12

Issued: Thu, Mar 09, 2017 at 8AM

Expires: Sun, Mar 12, 2017

Yet another round of gusty outflow wind has further scoured into our snowpack….mostly in in very high, exposed terrain.

Look out for new layers of wind slab recently top and cross loaded into lee terrain. Evaluate older slabs for bonding to underlying snow (crusts to facets to wind board) which could still be sensitive.

Above 2,500ft Moderate

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





Above 2000′
   Lee to northerly winds
 Near ridgelines, rollovers, and gully walls
Likelihood (Human Triggered):
 Small – Large
Danger Trend:
Forecaster Confidence:

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



intermountain-zone-iconInter-Mountain (Transitional) Specific: 

It has been 2 weeks since a snowflake has fallen from the sky and 11 days since the strong north winds started wreaking havoc on our snowpack. These extreme winds, that peaked near 90 mph, have scoured deep into older snow and drifted snow into low lying gullies, trees, crevasses and rollovers.  Many natural wind slab avalanches released throughout our region while few human triggered were reported, likely due to the inhospitable conditions. Wind affected areas have knife hard windslab, sastrugi, rain/melt-freeze crusts and wind scoured bare ground. The main concern is windslab over ice crust, buried surface hoar and near surface facets. Steep southerlies in the lower elevations are melting out to bare ground.

Thompson Pass gap winds still scouring into the snowpack.

Rain Crust from mid Feb.

Find more photos and observations at the bottom of the page. Sharing your observations creates an informed community that everyone benefits from at some point.

Recent Avalanche Activity

intermountain-zone-iconInter-Mountain (Transitional) Specific:  

Observed  Feb. 28:

  • Mar. 2: Many natural wind slabs have recently released off southerly and westerly aspects loaded by the NE wind.

Human triggered windslab below Crudbusters. Photo via Jed Workman

N Odyssey Gully Wall Slide

Long crown on rollover below 27 Mile Peak

  • Feb. 28: Natural D2 wind slab avalanche near the hairpin, on the south side of Odyssey.

  • Very obvious wind flagging on the peaks and sastrugi on the Deserted Glacier

  • Multiple Size 2 Wind Slab avalanches on South Aspects on Girl’s Mountain.


Recent Weather

See Maritime Zone for updated weather.

Additional Info & Media

Weather Quicklinks:

  • NWS forecast for Northeast Prince William Sound <here>
  • NOAA NWS spot forecast for Thompson Pass <here>
  • Thompson Pass RWIS weather station <here>
  • MP 30 Nicks (Happy) Valley weather station at 4200 feet <here> (scroll to Nicks Valley)
  • Valdez Glacier UAF weather station at 6600 feet <data here> <map here>
  • Further weather resources <here>


  • 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 Intermountain Forecasts.

Forecaster: Kevin Salys