An above-freezing layer is promoting the settling of the upper snowpack at alpine and treeline through the day. Watch for increased signs of instability such as natural avalanches as stability deteriorates with warm temperatures.
Variable winds have affected all aspects at higher elevations. Watch for windslab as you transition into wind-affected areas especially around ridge crests and in steep terrain.
Freezing levels reach well into the alpine Wednesday and Thursday causing surface snow to slowly deteriorate. With warm temperatures, even brief periods of direct sun could produce natural avalanches cycle on surface layers.
Elevated alpine temperatures are also weakening cornices. Stay back from cornices and minimize exposure time below cornices.
No new avalanches were reported in the region on Monday.
On Sunday, a few natural windslab avalanches were observed in the region. The largest was a size 2.5 on a north-northeasterly slope at 2100 m.
On Saturday, reports were limited to a few explosives cornice releases to size 2 and thin size 1 wind and storm slab releases in steep alpine terrain.
10-20 cm of storm snow has been redistributed by moderate winds, into deeper deposits in wind-affected terrain features. This sits over 50 cm of settling snow at higher elevations, tapering rapidly with elevation due to the recent warm temperatures.
Below 1600m new snow may sit directly on a thick melt freeze crust which is helping to strengthen the snowpack.
The lower snowpack is still being monitored by professionals. The late December crust is down 70 to 120 cm. This crust can be found in the alpine but is thin and breakable. Near the base of the snowpack, there is a weak facet/crust layer that formed in mid-November. Although unlikely, there remains a concern for large loads (e.g. cornice failure) to trigger or riders to trigger these layers in thin spots. In general, the current snowpack is thinner and weaker than is typical.
Tuesday Night
Mainly cloudy. Northwesterly ridge top winds 15-20 km/h. 1500m temperature low of -2C.
An above freezing layer develops from 1500 - 2500 m by morning.
Wednesday
Sunny with cloudy periods. Northwesterly ridge top winds 15 km/h gusting to 40 km/h. 1500m temperature high of +2C. The above freezing layer is present between 1500-2800 m and remains elevated overnight.
Thursday
Mix of sun and cloud. Northwesterly ridge top winds 15 km/h gusting to 40 km/h. 1500m temperature high of +2C. The above freezing layer is present between 1500-2500m.
Friday
Mix of sun and cloud. Northwesterly ridge top winds 20 km/h. 1500m temperature high of -2C. Freezing levels 1000 m.
More details can be found in the Mountain Weather Forecast.
