Haines Avalanche Center

Forecast Expired - 02/24/2022

Above 2,500ftModerate

1,500 to 2,500ftLow

Below 1,500ftLow

Degrees of Avalanche Danger

Low
Moderate
Considerable
High
Extreme

Avalanche Problems

Problem 1

Persistent Slab:

Aspect:  All Aspects

Elevation: Above Tree Line

 

Bottom Line: Winds that blasted from Haines Pass down into this zone over the last weekend have deposited snow in specific areas below prominent terrain features. Due to a reverse wind loading event, all aspects above tree line contain pockets of wind slab below ridge lines, peaks and passes. Currently, it is quite easy to identify these areas of concern as they are filled with soft, smooth snow whereas others areas are wind blasted, rimed and firm. While it may look tempting to get into these softer areas, they should be carefully evaluated. Natural avalanches are unlikely and human triggered avalanches are possible in these specific areas.

 

Travel Advice:

  • Avoid leeward slopes where the new snow was loaded and created surface wind slab.
  • Look for flagging and blowing snow near ridge lines.
  • Look for signs of snow that has been moved around by the wind (scouring and pillows of wind slab).
  • Look, listen and feel for shooting cracks, collapses and hollow sounds.
  • Avoid terrain trap areas such as cliffs and gullies, and areas where it is hard to escape off to the side.

 

Additional Consideration:

We believe deeper persistent layers are currently dormant. However, you could still trigger a persistent slab in thin or shallow snow even if we haven’t had recent feedback or avalanche activity. With the end of February comes a higher sun angle than we have seen for the last couple months. Surface warming will begin to be prevalent on solar days, especially around exposed rocks and creating thin and/or weak spots where you could trigger these deeper layers. Remember that persistent slabs are unpredictable and that tests and observations can be unreliable. A probe can be very helpful to determine snow depth and presence of deeper buried weak layers by noting resistance as the probe moves through the snow. Continue to use wide margins of safety, collect information and be patient when it comes to more committing terrain.

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Avalanche Activity

From 1/29 to 2/1, several reports came in of recent avalanches in the alpine. The common characteristics of these slides were wide propagation, and failing 2-5ft deep at the interface below the wind slabs from last week’s atmospheric river. We have strong reason to suspect these slides occurred on a buried surface hoar layer from 1/20. They happened on all aspects, at elevations from 3000 – 5000ft, and all were in wind sheltered areas below ridges, features, and starting zones. Slide were observed in the Transitional and Lutak zones.

4Winds zone.  SW.  4000-5000′

 

Near Mt. Kraus

The confluence of the Boundary and Saksaia glaciers above Glacier Creek. N.  ~4700′

Weather

Forecast:

The high pressure ridge from yesterday will keep some clear skies and lighter N winds. As the next front moves in from the south in the late morning, moderate southerly wind gusts will increase to moderate. No precipitation is expected and temps will be in the high 20s to low 30s.

Seasonal Summary:

  • Feb 16-19th light snow 3-4″ with freezing levels reaching 1,500′ strong south winds.
  • Feb 12-14th had freeze/thaw cycles that locked up the snowpack to ~4,000′.
  • Feb 5th-9th brought snow levels near 3,500ft, and 2.5-4″ of SWE with strong south winds.
  • Feb 1st-4th brought in 12-24″ of low density powder.
  • Jan 27-29 brought 1.5 – 2.4″ of SWE with freezing levels near 1500ft.
  • An Atmospheric river hit Jan 21-22. It brought in 2-7″ of SWE (2-5ft of snow above 2500ft, mostly rain below)
  • 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 **  122″*  2″ / 0.2″*  2″ / 0.2″* 0′ Moderate, S   0″ / 0.0″*
Flower Mountain @ treeline  67″  0″ / 0.0″  0″ / 0.0″ 0′ Moderate, S   0″ / 0.0″
Chilkat Pass @ 3,100ft  31″  0″ / 0″  0″ / 0.0″  0′  Light, SE   0″ / 0.0″

( *star means meteorological estimate )

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

Additional Information

Safe backcountry travel requires training and experience. You control your own risk by choosing where, when and how you travel. 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.

 

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