Above 2,500ft High
1,500 to 2,500ft Low
Below 1,500ft Low
Degrees of Avalanche Danger ?
Problem #1: Storm Snow
Around 0.8″ of precipitation has fallen in this zone in the last 24 hours, with heavy precipitation continuing today. The freezing level is around 4000ft. Above this level there is 6-12″ of heavy wet new snow sitting over a very weak old snow surface consisting of facets over a slick rain crust. Bonding of the new snow to this old surface is expected to be poor.
South winds will be increasing today, which will wind load the new snow into fresh storm slabs on north aspects. In some areas, these fresh slabs may build up to near 24″ thick. Any wind loaded areas will be sensitive to human triggering and need to be avoided. Natural and human-triggered avalanches are likely today.
Problem #2: Wet Avalanches
Wet slides will be a concern in the rain-on-snow elevations (all aspects between 3500-4500ft). It’s messy out there today, and all aspects above 28 degrees should be avoided. Also avoid gullies and terrain traps where avalanche debris tends to funnel.
Above 3500ft, snow depths generally range from 30-130cm. In the deeper areas, we have a well-bonded midpack frozen solidly to the ground. It hasn’t been terribly cold so far this year, so facetting between rain crusts has been minor so far. One exception is in high wind-swept areas where the snow is only about 30cm deep. In these areas, there are weak 2-3mm facets at the ground.
Recent Avalanche Activity
The last reported avalanche activity is from the rain-on-snow event on the 18-19th. D1-D3 wet loose and wet slabs came down from the most wind loaded north aspects above 4,000ft. Most of this activity was in the Lutak and Transitional zones where there was more snowpack and more rain.
We had a very wet October, with snow levels about 1,000ft above average, near 3500ft. Above that level there was good accumulation, with almost nothing below it. This trend has continued into November.
|Snow Depth [in]||Last 48-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
|10″||5″ / 1.00||5″ / 1.00||4000||light, SE||0″/ 0.50 *|
Flower Mountain @ treeline
|12″||5″ / 0.70||5″ / 0.70||4000||mod, SE||0″/ 0.50 *|
Chilkat Pass @ 3,100ft
|5″||3″ / 0.45||3″ / 0.45||4000||mod, SE||0″/ 0.50 *|
( *star means meteorological estimate )
Additional Info & Media
If you get out riding, please send in an observation!
Start the season with fresh batteries in your beacon, and do a rescue practice with your partners. Always carry a beacon, shovel, and probe, and KNOW HOW TO USE THEM.
Practice good risk management, which means only expose one person at a time to slopes 30 degrees and steeper, make group communication and unanimous decision making a priority, and choose your terrain wisely: eliminating unnecessary exposure and planning out your safe zones and escape routes.