Above 2,500ft Moderate
1,500 to 2,500ft Low
Below 1,500ft Low
Degrees of Avalanche Danger ?
Below treeline the snow is frozen hard. Above 3,500′, there is around 4″ of new snow on top of a frozen-solid rain crust (around 2″ thick).
Problem #1: Wind Slab
Location: Wind loaded slopes and cross-loaded terrain features/gullies, above 3,500ft. There was a little fresh snowfall above 3,500ft Tuesday. It has allowed for some agreeable riding. South winds earlier this week followed by moderate north winds the last few days will have whipped the new snow around into recent slabs. This will especially be true on high and exposed slopes, and around ridgelines and summits. It will be possible to trigger wind slabs in this new snow anywhere it is blown in deeper than a few inches. Test slopes and hand shears will be helpful as you judge the danger from slope to slope. Avoid areas of cohesive slab.
Stick to areas where the new snow is still soft and protected. Always practice good travel techniques, utilizing safe zones, escape routes, only exposing one person at a time to slopes over 30 degrees.
Recent Avalanche Activity
During/after the storm on the 16th, there was a widespread avalanche cycle with most slopes steeper than 30 degrees running. Most slides were size 2 or 3, with a few to size 4. Observed crowns ranged from about 30-100 cm thick, sliding on various weak layers from the previous month.
Clouds and light snow should be the trend this week. Accumulations could reach perhaps 4-8″ over the mountains by the end of the week.
|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
|35″*||0″ / 0.00*||0″ / 0.00||1000||light, N||0″/ 0.00 *|
Flower Mountain @ treeline
|31″||0″ / 0.00||0″ / 0.00||1000||light, NW||1″/ 0.10 *|
Chilkat Pass @ 3,500ft
|20″*||0″ / 0.00 *||0″ / 0.00 *||1000||light, NW||0″/ 0.00 *|
( *star means meteorological estimate )
Additional Info & Media
If you get out on the snow, send in your observations!
We will be providing an AIARE Avalanche Level 1 Class this winter in Haines, February 23-25, 2018