Summary
Confidence
Fair - Timing, track, or intensity of incoming weather is uncertain
Weather Forecast
A polar warm front stalling north of the region will bring moderate to heavy precipitation to the surrounding areas Sunday. However, the South Columbia will largely be "protected" from the action by a lingering ridge of high pressure. I expect scattered flurries in the region Sunday with precipitation values in the 5 - 10 cm range. The western edge of the forecast region will likely receive a bit more. Freezing levels rise to 1500m or so Sunday as the warm front affects the area. The trailing cold front associated with the system moves in late Sunday/early Monday bringing lower freezing levels and another 5 -15 cm of snow. Expect strong SW winds at & above treeline Sunday with a daytime high of 0 C @ 1500 m.
Avalanche Summary
The new snow has been sluffing in steep terrain & a few natural avalanches to size 2.5 involving the new snow (likely wind affected) have been reported on almost all aspects at and above treeline.
Snowpack Summary
The region has received 30 - 70 cm of snow out of the latest storms. In some locations, this new snow rests on a buried surface hoar layer from Jan. 03. Strong SW winds have redistributed the new snow into wind slabs which can be found in varying thicknesses on NW through SE facing slopes. The mid-December surface hoar layer remains a concern and is now buried 90 - 150 cm below the surface. While fairly wide spread, it seems to be most sensitive on South through East facing aspects around treeline. In some locations a crust can be found from valley bottom up to about 1600 m that formed with the recent warm temperatures.
ghelgeson,
Avalanche Canada
