Backcountry Avalanche advisory
Updated May 5, 2006 6:45pm
Synopsis..A Ridge Of High Pressure Over The Coast Will Begin To Weaken Tonight As A Frontal System Approaches From The Northwest. The Front Will Spread Cloud And Precipitation Across The South Coast Mountains Saturday Afternoon And Evening.
Backcountry Avalanche advisory Wednesday, May 3, 2006
Alpine: LOW
Treeline: LOW
Below Treeline: LOW
The hazard rating will increase with solar effect and daytime warming.
Travel Advisory: At higher elevations, yesterday's surface layers have set up with the cool overnight temperatures as travel conditions will be variable. Stay Well back from mature cornices; they will become sensitive as temperatures increase throughout the next few days.
Avalanche Activity: You can expect to see the loose, surface-snow begin to sluff as warming temperatures and solar radiation have their way with it. Explosive testing on Monday caused a cornice fall that then triggered a 1m deep slab on a northern aspect which ran on the 060412 crust. A similar slab at approx 1900m on the North aspect of Mt. Currie was caused by Saturday morning's heavy rain. The interface that this crust offers will be with us for some time yet.
Snowpack: Last night's cool temperatures created a very stiff crust on all aspects and elevations. The loose, surface-layers will rapidly destabilize today as temperatures warm, and the underlying crust will provide a fast sliding layer. In terrain where the crust is on the surface the destabilization process will take longer to occur. The snowpack at lower elevations will trend towards isothermal as the temperatures increase this week -- avoid slopes where you are breaking through into the mushy snow.
Weather: With this ridge of high pressure building today we can expect mainly sunny skies and increasingly warm temperatures throughout the week. Freezing levels will be rising to mountain top by Wednesday and Thursday is forecasted to be Hot. The models show the ridge breaking down by Friday and a weak frontal system coming onshore, which will bring with it cloud cover and precipitation. Whistler Mtn. Snow Safety
