South Columbia

Continued new snow and wind will bump the alpine danger up to Considerable. Watch for natural cornice falls and remote triggering of wind slabs.

Moderate - Intensity of incoming weather systems is uncertain on Thursday

Some moisture trapped in the south to north flow coming out of Washington State should bring 3-5 mm of precipitation (5-10 cm of snow at treeline) overnight, and another 5-7 mm of precipitation during the day on Thursday. Some of the western upslope areas may see enhanced snowfall. Winds are expected to be light from the southeast and alpine temperatures should remain around -5. High pressure with light winds and cooler air should move into the region from the north on Friday. Some flurries may continue on Friday and Saturday with periods of broken skies and alpine temperatures around -10.

Natural cornice avalanches and natural and skier controlled wind slab avalanches up to size 1.5 have been reported. Most of these have been on northerly aspects in the lee of local winds. Winds have been generally easterly, but some areas have had locally more southerly winds due to terrain.

10-25 cm of new snow is now sitting on the mix of surface hoar, near surface facets, and sun crust that was left behind after the recent clear and warm weather. Easterly winds have transported the new snow and some of the loose snow available into wind slabs at higher elevations. The new snow is reported to be loose and unconsolidated except where the wind slabs exist. Forecast warming with continued light snow may settle the storm snow into a cohesive slab. The mid and lower snowpack is generally well settled and strong.