Avalanche Forecast
Issued: Mar 12th, 2019 4:12PM
The alpine rating is Storm Slabs and Persistent Slabs.
, the treeline rating is , and the below treeline rating is Known problems includeSummary
Confidence
Moderate -
Weather Forecast
TUESDAY NIGHT: Cloudy. Dry. Light west wind. Treeline temperatures around -6 C.WEDNESDAY: Moderate to strong south wind. Treeline temperatures around -8 C. Snow starting late in the day and overnight; 10 to 15 cm accumulations by Thursday morning. Cloudy.THURSDAY: Moderate to strong southwest wind. Treeline temperatues -5 to -10 C. Light snow with an additional 5 to 10 cm. CloudyFRIDAY: Moderate south wind. Warmer with treeline temperatures approaching zero. Trace new snow. Cloudy.
Avalanche Summary
One size 2 windslab in the north of the region is worth noting: it was remotely triggered from 100 m away suggesting some sort of a persistent slab structure that won't heal overnight.In the south part of the region clouds limited observations but avalanche reports include numerous natural size 2 avalanches on all kinds of terrain 35 degrees or steeper, numerous remotely triggered size 2 slides. I suspect we'll learn more when the visibility improves and people see more terrain.
Snowpack Summary
Monday's widespread and reactive storm slabs and wind slabs should be settling down by Wednesday with the exception of colder, more northerly areas which have significantly more "wintery" temperatures. Expect instabilities to last longer in places like Bear Pass or Ningunsaw.The 40 to 60 cm of storm snow buried a wide variety of surfaces with the key idea being they're pretty much all crappy. Rule of thumb: the longer snow is exposed on the surface the less likely it'll bond when buried. Recently covered were surface hoar, sun crusts, and a widespread weak faceted (sugary) upper snowpack. It seems the old surfaces (aka Feb 19 surface hoar / facets) were as much the critical weak interface as the bottom of the storm snow.The lower snowpack is generally strong.
Problems
Storm Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Persistent Slabs
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Valid until: Mar 13th, 2019 2:00PM