Haines Avalanche Center

Forecast Expired - 12/02/2021

Above 2,500ftConsiderable

1,500 to 2,500ftConsiderable

Below 1,500ftModerate

Degrees of Avalanche Danger

Low
Moderate
Considerable
High
Extreme

Avalanche Problems

Problem 1

Wind Slab:

Aspect: Most likely on W-NW-N aspects and below terrain features

Elevation: Mainly Treeline and above

 

New snow this week is about 5-12″, and SE winds were strong last night. Winds may decrease during the day today, but you are likely to encounter fresh wind slabs and active wind loading in the alpine. Identify wind-drifted snow by looking for stiff or hollow surface snow, and looking for cracking, whumphing and blowing snow – treat these areas as highly suspect. You can find safer conditions in wind-protected areas with softer snow. 

 

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Persistent Slab:

 

Confidence: Low-Moderate

Elevation: From 2,500ft to 4,000ft

 

Look and listen for deep whumping!

 

The lower snowpack in all zones contains one or more rain crusts from mid October. Weak facetted snow has formed above and below the crust, and a lot of new snow has fallen in the last 2 weeks. It will be possible to trigger an avalanche on this layer, about 1m or deeper. We expect this October rain crust will be a lasting problem as we go into winter so keep your guard up! This layer exists on all aspects, but observations are limited and uncertainty is high.

 

What is the best way to manage this risk? We can simply avoid alpine terrain that is about 30 degrees and steeper. Be aware that venturing on these steeper alpine slopes is relatively high risk currently. Persistent slabs require a wide safety buffer.

Another way to reduce your exposure to these deep weak layers would be to stick to areas of deeper snowpack (>1m deep). But be wary of hidden rocks that can act as trigger points, and thin areas around the margins of a slab.

 

Likelihood:

  • Almost Certain
  • Very Likely
  • Likely
  • Possible
  • Unlikely

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Weather

October brought heavy snow in the alpine, followed by a few rain/sun crusts. November has brought regular heavy snowfalls, adding up to 70+ inches so far. Winds have alternated between NW and SE.

Over the last week, temperatures hovered near freezing in the mountains, and winds have been from the SE. Snowfall this week has been around 6-12″. A few more inches of snow is possible Thursday.

 Snow Depth [in] Last 24-hr Snow/SWE [in] Last 3-days Snow/SWE [in]  Today’s Freezing Level [ft]  Today’s Winds Next 24-hr Snow/SWE
Mount Ripinsky @ treeline **   67″ *  7″ / 0.60*  11″ / 1.00*  0′  Mod, SE  2″ / 0.12*
Flower Mountain @ treeline  49″  5″ / 0.50  5″ / 0.50  0′ Mod, SE  1″ / 0.10*
Chilkat Pass @ 3,100ft  29″  5″ / 0.20  7″ / 0.30  0′ Mod, SE  1″ / 0.15*

( *star means meteorological estimate )

** The Ripinsky weather station is currently down, we will try to get it working again soon

Additional Information

FREE Avalanche awareness and companion rescue practice first Friday December 3rd at the Haines Library from 3:30-5:30pm. This life-saving training is sponsored by the Alaska Department of Public Safety and Alaska State Troopers and hosted by the @hainesavycenter. Bring your beacon, shovel and probe for hands-on practice and informational presentation. For all ages, ability levels and user ground. Let’s kick off the season with knowledge and safety. Join us for Learn and Return!

Beware of deep treewells which can trap a person. It’s deep out there.

 

In November, onX Backcountry is donating $10 of every membership to support forecasting. By leveraging their Slope Angle and Avalanche Forecast layers you’ll have access to the tools that help  inform safer backcountry travel this year.

 

Practice like you play. Make sure all your rescue gear is fully functional and your beacon has NEW batteries. Make sure 1) everyone in the group has a functioning beacon, shovel and probe 2) knows how to use them and 3) has trained in companion rescue in the last year. Keep your skills fresh. If you head into the hills, watch out for red flag avalanche conditions, natural avalanches, whoomphing or collapsing, and shooting cracks.

 

Education Video Links:

Announcements

Click the –Full Forecast– button below for more details. We need your observations! FREE Avalanche awareness and companion rescue practice first Friday December 3rd at the Haines Library from 3:30-5:30pm.