We will be providing an AIARE Avalanche Level 1 Class this winter in Haines, February 23-25, 2018
Above 2,500ft None
1,500 to 2,500ft None
Below 1,500ft None
Degrees of Avalanche Danger ?
Avalanche season is here. We’ve already had a significant skier-triggered avalanche reported (see below). Early season can be sketchy: several avalanche fatalities have occurred this time of year.
Snow depths are around 10cm at 3,500ft, ranging up to 100cm in wind loaded areas above 5,000ft. October brought less than half of the normal 9″ of precipitation we would expect for the month. The result is quite variable snow depths due to thin snowpack and windy conditions.
Temperatures above treeline are around 5 – 10°F. This has caused faceting of the thin snowpack above treeline. These 2-3cm facets are setting up a weak base to hold up future heavy snows. Keep this in mind as November progresses and snow depths increase.
For now, keep your guard up, and feel around for slabby, layered snow which may be unstable. Probe and dig around. If you find cohesive slabs sitting above softer, weak layers, you have everything you need for an avalanche. Remember that conditions are quite variable right now, and stability will vary from slope to slope. Start the season with fresh batteries in your beacon, and practice with your beacon, shovel, and probe.
If you get out on the snow, send in your observations! We will start regular forecasting when enough obs start coming in.
Recent Avalanche Activity
October 28th: First rider-triggered slide reported from the peak north of Nadahini (“Sunny Bunny”). D2 soft slab ran in storm snow from Oct 26-27. Nobody caught or injured. [ SS-AR-D2-R3-S ] South aspect @ 6,200ft.
Small – Moderate natural avalanche activity is occurring during/after storms. So far it has been mostly loose-snow slides, with a few slab avalanches as well.
Alpine temperatures have been hovering around -12°C (+10°F) for the last several days. North winds have been moderate with occasional blowing snow. This will continue for the next week or more, even as a weak storm comes in Friday with 3-6″ of new snow.
|Snow Depth [in]||Last 24-hr Snow/SWE [in]||Last 48-hr Snow/SWE [in]||Today’s Freezing Level [ft]||Today’s Winds||Next 24-hr Snow/SWE|
Mount Ripinsky @ treeline
|0 / 0.00||0 / 0.00||0||mod, N||6″ / 0.40 *|
Flower Mountain @ treeline
|0 / 0.00||0 / 0.00||0||mod, NW||5″ / 0.25 *|
Chilkat Pass @ 3,500ft
|4||0 / 0.00 *||0 / 0.00 *||0||mod, NW||3″ / 0.15 *|
( *star means meteorological estimate )
October 5th: 4-10″ of snow fell above 4,500ft.
October 13-15th: 6-12″ of snow fell above 2,500ft in the Lutak and Transitional zones, less snow fell in the Pass zone.
October 18-24th: 2-6″ of snow fell above 2,000ft
October 26th-27th: A warm tropical system brought heavy snow above 3000ft, transitioning to heavy rain as snow levels peaked near 6000ft before dropping again. There was a net gain of around 30cm of new snow above 5000ft.