Avalanche Center Tsaina Lodge Spring Full Moon Bon Fire FUNraiser
Friday April 14 presenting Acoustic Avalanche
Above 2,500ft Moderate
1,800 to 2,500ft Low
Below 1,800ft Low
Degrees of Avalanche Danger ?
|SUNDAY||MONDAY||TUESDAY & WEDNESDAY|
Likelihood (Human Triggered): Possible
Size: Small – Large
Danger Trend: Steady
Forecaster Confidence: Poor
AVALANCHE PROBLEM SCALE DESCRIPTORS:
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
AVALANCHE PROBLEM TOOLBOX <here>
Continental (Interior) Specific:
Do your best to evaluate and avoid old firm wind slabs that are harboring poor structure: strong over weak. There have been recently reported significant collapses (as large as whole basins whumphing) in areas on the northerly and easterly outreaches of our Inter-mountain zone, and into the Continental zone. Deep persistent slab problems are challenging to predict: have a lower probability of triggering, but with serious consequences.
Last week’s series of convective storms across the region deposited significant variation of new snow throughout the region. Cordova reported 8 inches at sea level and 2 feet above 1000′. Valdez received 2 inches with 1 foot at Thompson Pass and in the upper elevations of the maritime snow climate zone. Kenny Lake has recieved an inch or two almost daily through the past week.
Conditions are a shallow and weak snowpack with a variable mix of rain crusts and wind packed rounds. The last reported human triggered avalanche was March 11th on Mt. Tiekel, a near ridgetop windslab size D2. Testing March 15 near MP 50 (on the shoulder of Mt. Tiekel) demonstrated poor snow structure with easy-moderate propagation results. Knife hard wind slabs and firm rain crusts will now serve as bed surfaces.
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
Continental (Interior) Specific:
- March 25: reports of upper elevation (>4500′ elevation) human triggered windslab to a foot thick releasing off steep slopes.
- March 25: Several reported natural and one remotely triggered soft slab avalanche up to D1.5 on southerly aspects between 4,500′-5,500′.
- Reported March 24: Many significant collapses, as large as whole basins whumphing, in areas on the northerly and easterly outreaches of our Inter-mountain zone, and into the Continental zone. Deep persistent problem
- March 11 report of upper elevation skier triggered avalanche that ran on a previously released slope (March 3rd?) which has reloaded. The hard slab avalanche fracture crown was two feet deep, propagated 400 feet across the start zone, and ran 1000 feet. The skier was able to ski off the moving slab and wasn’t captured.
- March 7 report of two size D1 soft slab avalanches (3500’ SW 20cm and 4000’ NE 15cm). Plus long running dry loose and several collapses on low angle terrain.
See Maritime Zone for updated weather.
Additional Info & Media
- 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>
SNOW CLIMATE ZONES:
- Maritime (Coastal) – from the Port of Valdez to Thompson Pass, all waters flowing into Valdez Arm and everything south of Marshall Pass.
- Inter-mountain (Transitional) – between Thompson Pass and Rendezvous Lodge.
- Continental (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)
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: http://www.