Wednesday – Saturday 3/29-4/1

Issued: Wed, Mar 29, 2017 at 8AM

Expires: Sat, Apr 01, 2017

18 inches of new snow over the last 72 hours. Be aware of small terrain features that could slide and bring you over or into a terrain trap.

Avalanche Center Tsaina Lodge Spring Full Moon Bon Fire FUNraiser

Friday April 14 presenting Acoustic Avalanche

Above 2,500ft Considerable

1,800 to 2,500ft Considerable

Below 1,800ft Moderate

Degrees of Avalanche Danger ?

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

Avalanche Danger Rose ?

Avalanche Problems ?

Problem Details

WEDNESDAY THURSDAY FRIDAY & SATURDAY

DANGER SCALE

 

STORM SLAB

Elevation: All
Aspect: All
Terrain: All
Sensitivity: Responsive
Distribution: Widespread
Likelihood (Human Triggered): Possible
Size: Small – Large
Danger Trend: Increasing
Forecaster Confidence: Good

WIND SLAB:
Elevation:  
Above 3000′
Aspect:
   Lee to northerly winds
Terrain:
 Near ridgelines, rollovers, and gully walls
Sensitivity:
  Responsive
Distribution:
 Specific
Likelihood (Human Triggered):
Likely
Size:
 Small – Large
Danger Trend:
  Increasing
Forecaster Confidence:
   Fair

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>

SNOWPACK DISCUSSION:

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

On the summit of the pass another 8” has fallen in the last 24 hours totaling up to 18” over the last 72 hours. The further you get from the pass the new snow levels seem to dramatically decrease. This has been a trend all season, with most of our storms hammering the maritime zone, while leaving the intermountain/continental zones high and dry.

You are most likely to trigger a storm slab today, potentially large enough to bury and kill you. This slab could be over 3 feet thick with winds added in the mix. Yesterday there were reports of avalanches and cracking on the Road Run, which is not uncommon during and after a storm.

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:  

  • March 28 an Avalanche was reported on the Road Run.
  • Human triggered avalanches sizes D2-2.5 likely on steep wind affected rollovers, ridgelines, and gully walls.
  • March 25 reports of upper elevation (>4500′ elevation) human triggered windslabs to a foot thick releasing off steep slopes. With a D1.5  remotely triggered slide on a southerly aspect between 4,500′-5,500′.

    Loose snow triggered soft slab: ~30cm crown. Gully One (Vertigo)

  • March 24: Small D1 R1 skier triggered wind slab on the west facing wall of Snatch (Gully 2). Recently loaded by NE outflow winds

Recent Weather

See Maritime Zone for updated weather.

Additional Info & Media

Weather Quicklinks:

SNOW CLIMATE ZONES:

  • 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

thompson-pass-ski-runs

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

climate-zones-topoclimate-zones-satellitegoogle-earth1

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: http://www.avalancheforecasts.com/

Posted in Intermountain Forecasts.
Kyle Sobek

Forecaster: Kyle Sobek