Haines Avalanche Center

Forecast Expired - 01/21/2022

Above 2,500ftHigh

1,500 to 2,500ftHigh

Below 1,500ftHigh

Degrees of Avalanche Danger

Low
Moderate
Considerable
High
Extreme

Avalanche Problems

Problem 1

Wet Avalanches:

Aspect: All

Elevation: Below freezing levels ~2500-3000′

 

Bottom Line: Avalanche danger spikes to HIGH with heavy precipitation, warming temperatures, south winds and rain on snow during the atmospheric river event this weekend. Anywhere at or below the freezing level, natural wet avalanches are very likely to almost certain. This includes the potential of liquid water loosening bonds not only at the surface, but deeper down on buried weak layers, or at the ground and could produce wet slab avalanches (see persistent problem below).

 

 

Travel advice: With the nature of wet avalanches and the intensity of the incoming storm, no reliable travel technique through avalanche terrain will keep you safe. Avoiding any slopes greater than 25 degrees, connected terrain, run out zones and terrain traps are vital to not getting caught in a potentially small to large slide. Very dangerous conditions exist. Travel in avalanche terrain is not recommended.

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Persistent Slab:

Aspect: All

Elevation: All

 

Bottom Line: Heavy precip, rapid loading and warming temperatures will add significant stress to weak layers buried in the snowpack. Natural avalanches will be likely and human triggered avalanches are very likely. With multiple strong over weak layering throughout the snowpack surface avalanches could still step-down to trigger deeper persistent weak layers, which could cause wide propagation and very large avalanches. This storm has the potential to produce the largest avalanche cycle of the season.

 

Travel advice: With the nature of wet avalanches and the intensity of the incoming storm, no reliable travel technique through avalanche terrain will keep you safe. Avoiding any slopes greater than 25 degrees, connected terrain, run out zones and terrain traps are vital to not getting caught in a potentially large to very large slide. Very dangerous conditions exist. Travel in avalanche terrain is not recommended.

 

Lingering Persistent Weak  Layers:

  • Northerly aspects that escaped the wind and are harboring weak surface snow were loaded by south winds Jan. 10th
  • Facets formed on the surface at the end of the arctic outflow event (around Jan, 7th) from high daily temperature swings.
  • Surface hoar and near-surface facets from Dec 18th may have been preserved in wind-protected areas
  • The Nov. 25th ‘Thanksgiving brittle crust‘ was found near 3,200’ and below
  • Toward the very bottom: early season snowfalls and crusts linger and are very difficult to trigger but are still of concern for step-down potential.

 

Test pit profile and results from Jan. 17th on Four Winds Mountain with mid-Dec thick buried facets down 75cm

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

01/15/2022 – An observation from Four Winds Mountain reported a collapse and a remote trigger of an approximately 200′ wide avalanche at 3,000′ on a northern aspect. It was estimated to run a couple hundred feet but low visibility kept observations to a minimum

 

01/17/2022 – On solar aspects past Mosquito Lake and above Lutak Inlet small point releases were reported above treeline on steep alpine features.

Weather

Forecast:

A very wet and warm atmospheric river hits Friday-Saturday. Precipitation amounts of 3-5″+ will cause flooding concerns to increase in the valleys, while the upper elevations receive multiple feet of heavy wet snow. Snow levels are likely to rise to near 3000ft Saturday. This will be a good weekend to stay home, or out of avalanche terrain.

Seasonal Summary:

  • Jan 9th-15th brought 24-48″ of new snow in the alpine, with some light rain up to 3,500ft, followed by heavier rain up to 2000ft.
  • Very strong NW winds and arctic temperatures blasted the area the first week of January
  • Jan 1st: New snow (20″ in Lutak, 7″ Transitional zone) buried any preserved surface hoar.
  • Moderate NW winds hit exposed slopes Dec 19-20th
  • Surface hoar formed on all aspects and elevations Dec 17-18th
  • December brought in about 2-5 feet of snowfall (highest in Lutak zone), and a few strong NW wind events
  • November brought consistent heavy snowfalls, cold weather, and SE winds
  • October brought heavy snow in the alpine, followed by a few rain/sun crusts
 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 **  73″*  0″ / 0.15*  5″ / 0.40*  3000′  Mod, SE  24″ / 3*
Flower Mountain @ treeline  57″  0″ / 0.00  1″ / 0.10  2500′  Mod, SE  18″ / 2*
Chilkat Pass @ 3,100ft  18″  0″ / 0.00  1″ / 0.10  2500′  Mod, SE   12″ / 1.5*

( *star means meteorological estimate )

** The Ripinsky weather station is in need of repair, and will likely be down until Summer.

Additional Information

Ride rescue ready. Be prepared for an emergency. Prevent hypothermia. Carry bear spray. Winter is a high consequence environment.

Become a sustaining Haines Avalanche Center Member by clicking the poster or visiting alaskasnow.org/joinHAC. Support local forecasts, observations, education and weather stations. Join a community of winter recreationalists. Benefit from collective knowledge and skills. Help keep your friends and family safe in the backcountry. Get a free limited edition mountain buff, or neck gaiter with a $50 membership (first 20 members!).

 

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:

Alerts

Avalanche danger spikes to HIGH with heavy precipitation, warming temperatures, south winds and rain on snow during the atmospheric river event this weekend. Very dangerous conditions exist. Travel in avalanche terrain is not recommended.