Expect changing conditions as you gain elevation in the wake of this storm,. Low elevations hold wet snow and higher elevations hold storm slabs that may be reactive to human triggers.
Storm snow above 1700 m is generally bonding well to the snow below. Expect human triggering to still be possible as conditions clear. Expect the greatest hazard to be in wind loaded features around ridgelines from southwest winds.
Expect loose wet avalanches to still be possible to trigger, even after the rain has stopped. More reactive conditions exists where wet snow sits over a smooth crust.
Watch for where surface snow is heavy and wet.
The wet weather finally exits Thursday. Expect warm temperatures to continue Thursday before finally cooling off for the weekend.
WEDNESDAY: Up to 10 mm of rain is possible overnight with freezing levels remain around 2000 m. Moderate southwest winds.
THURSDAY: The front exits leaving clearing skies and no significant precipitation expected. Freezing levels remain at 2000 m, with light northwest winds.
FRIDAY: Mostly sunny with strong southwesterlies increasing over the day. Freezing levels rise from 1500 m to 3000 m
SATURDAY: Freezing levels remain below 1500 m. A mix of sun and cloud with no precipitation expected. Moderate winds from the west.
Naturally triggered storm slabs to size 1.5 were observed at high elevations in steep terrain features lee to the strong southwest winds on Tuesday.
Low elevation naturally triggered wet avalanches were observed throughout the highway corridors to size 2 throughout the duration of this storm.
20-60 cm of mixed precipitation has created a variety of surface snow conditions. Alpine areas have seen strong southwest winds creating deeper deposits in north through east facing slopes. At lower elevations the precipitation fell as rain creating a saturated upper snowpack.
This recent precipitation adds to the 50+ cm of snow that has fallen since January 1, which may overly sugary faceted grains that formed during the cold spell in late December.
Around 80 to 200 cm deep, a weak layer of faceted grains may be found above a melt-freeze crust that formed in early December. The layer is most prominent between 1700 and 2100 m. Observed avalanches on this layer are sporadic and isolated. The most likely place to trigger it would be in thin, rocky snowpack areas. The lower snowpack is well-settled and strong.
