This Bulletin Valid Until: Friday December 8th, 2017 @ 6 pm.
Confidence: Moderate - no alpine snow pack observations and most obersvations limited to Eastern Central Vancouver Island.
Main Concerns: (Avalanche problems)
Loose Wet- Rising temperatures and freezing levels are likely/very likely to produce avalanches from small to large, especially on solar aspects at all elevations.
Wet Slab- Recent storm snow and wind loaded areas overlying the upper rain crust are likely to produce wet slab avalanches with the forecasted warming. These avalanches have the potential to be large/very large in the upper treeline to alpine.
Travel/Terrain Advice: Very high temperatures and freezing levels and no overnight freezing of upper snow pack will result in very moist to wet snow that provides little support to travelers. Be aware that even small loose wet avalanches can push one into or over terrain traps such as depressions, cliffs, and trees. There is potential for large to very large avalanches starting in treeline and alpine terrain to impact below treeline elevations. Use caution when crossing large avalanche paths in all elevations. Watch for early season hazards such as exposed creeks, stumps, and tree wells especially below treeline.
Past Weather: Vancouver Island has seen little to no precipitation, light to moderate SW through SE winds and temperatures ranging from -7oC to +6oC. Freezing levels across the forecast region have ranged from sea level to 2300 m.
Avalanche Summary: Loose wet avalanches at treeline and below treeline on exposed solar aspects with pinwheeling and tree bombs.
Snow Pack Description:
Surface - Thin unsupportive melt freeze crust on solar aspects at all elevation, in some shaded areas snow remains cold
Upper - Wind loaded pockets bonding moderately to an upper crust on NW-NE aspects at treeline and alpine. Scoured and pressed surface on windward slopes exposing the crust
Mid - Well settled crust complex
Lower - Well settled
Weather Forecast: Temperatures and freezing levels will remain high with potential freezing levels of up to 3600 m with the persistent high pressure system. Expect a temperature inversion for the duration of the forecast period with low level clouds and morning fog near the ocean.
Wed - No new snow. Winds light SE
Freezing level to 2800-3600 m
Thur - No new snow. Winds light to moderate SE
Freezing level to 2500-3600 m
Fri - No new snow. Winds light to moderate SE
Freezing level to 1200-3600 m
Prepared by Bill Phipps