Haines Avalanche Center

Forecast Expired - 11/28/2020

Above 2,500ftHigh

1,500 to 2,500ftConsiderable

Below 1,500ftConsiderable

Degrees of Avalanche Danger

Low
Moderate
Considerable
High
Extreme

Avalanche Problems

Problem 1

Storm Snow:

Avalanche danger will be rising fast today as the storm comes in. We expect new storm slabs over a foot deep by evening. The new snow will be upside-down and weak underneath. Below the new snow, there are known weak interfaces within older storm layers (45-60cm deep). Be careful to avoid terrain traps where small amounts of snow can pile up deeply. Slopes steeper than 30 degrees should be avoided. Steep openings in the trees will be likely places to trigger a slide.

(Click to enlarge graphic to read more…)

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Problem 2

Persistent Slab:

In areas above treeline, depth hoar exists at the ground. There are also 2 melt-freeze crusts just above this depth hoar and in the midpack. Any of these crusts can act as a bed surface and a weak interface within the old snow. This will be a problem on all aspects. Be especially cautious of steep, heavily wind-loaded areas above treeline, and unsupported slopes. Convexities, where there is a steep rollover, will be a likely place to trigger a deeper slab that runs to the ground with high consequences. This kind of danger is tricky and can be hard to manage, so a wide safety margin is recommended.

(Photo from Lutak Zone, 11/15, 2500ft, NE aspect)

 

Likelihood:

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

Size:

  • Historic
  • Very Large
  • Large
  • Small

Trend

  • Increasing
  • Steady
  • Decreasing

Weather

Heavy snow last weekend brought a fresh 26″ in the Lutak Zone, 19″ in the Transitional Zone, and 9″ at the Pass.

The storm track looks energetic for the next week, with several strong/wet storms on tap. Saturday-Sunday we expect 14-20″ of new snow, with some rain mixed in below 1000ft. Monday night-Tuesday looks very wet, with multiple feet of new snow above the snowline, which should start at sea level and then rise quite high. Stay tuned!

 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
  46″ 0″ / 0.00 3″ / 0.30 0 -> 1000 light, NW 20″ / 1.75    *
Flower Mountain @ treeline
  25″ 0″ / 0.00 2″ / 0.30 0 light, NW 15″ / 1.30    *
Chilkat Pass @ 3,100ft
  7″ 0″ / 0.00 2″ / 0.10 0 light, NW 10″ / 0.90   *

( *star means meteorological estimate )

Additional Information

It’s time to start thinking avalanche. Dust off your gear and make sure it is fully functional. Put new batteries in your beacons! Do a beacon practice to start the season and keep your skills fresh. If you head into the hills, watch out for avalanche conditions, and be especially careful of rocks and hidden hazards like crevasses beneath the snow. WEAR A HELMET!

Education Video Links:

Announcements

We have begun periodic conditions updates for winter 2020/2021. Click the + Full Forecast link below for each zone to read more.