Vancouver Island Avalanche Bulletin

DANGER RATINGS (Make sure you understand the danger level meanings)

Outlook	Monday	Tuesday	Wednesday
Alpine  1560 m 2200 m	*MODERATE	MODERATE	MODERATE
Treeline	MODERATE	MODERATE	LOW
Below Treeline	LOW	LOW	LOW

Confidence: Good. (Except precipitation amounts and timing. Expect a surge of moisture Monday more West to Central Island South 25 to 30 mm. This could spike the local area Danger Ratings, Forecast if this falls in the form of rain and exceeds 25 mm.

* Timing and Distribution of Hazard during 'Spring' or 'Melt/Freeze' period 'ISO Thermal' period: Key factors to monitor and observe:

• Air Temperatures
  
• Affects of direct Sun
  
• Snow surface conditions (Snow Temperatures ISO Thermal conditions)
  

 Main Concerns:

• Cornice Fall                                                           Any aspects except South.
• Loose Wet surface slides                                  Widespread
• Deep slab on February crusts                        Alpine Leeward

WEATHER

This past few days and week 'Above Freezing Temperatures' have persisted 'At and  below Tree line' (2 degrees C to 5 air and higher on solar aspects rocky areas . Some nightly refreezing has taken place at higher elevations and specific cool aspects.  Precipitation came in the form of drizzle and mixed rain/snow and we saw less than 10mm for the past 3 three days. Wind was not a big factor switching from South to West and a bit calm North.

Sunday eve into Monday AM steady showers with some stiff South winds, 20mm plus more showers expected into Tuesday*. Freezing levels drop a bit by Wednesday until the sun comes out. The Light to Moderate winds start South Mod and switch West by Later Monday hey should ease to the West North West by Wednesday  .

Avalanche Activity:

Primarily surface instabilities, wet loose surface avalanches and continued cornice falls, some as large as size 2.

Snowpack:

A Melt Freeze cycle is wide spread. Over night refreezing ranges from not freezing a lower elevations to freezing lightly to freezing a little harder up high. ISO-thermal is the term used to describe snow that has turned to slush and is all one temperature. At 1440 m it has not frozen since the 14th April.

The old snow layers (February crusts) could cause a concern as the snow pack above is loosing strength fast and large natural triggers such as cornices could take off all the snow we have had since March down 50 to 2.5 meters deep.

In the worse case: a Cornice Falls and triggers a large slope down into the March/April snow which then steps down to the February crusts. This could be up to 3 meters deep with the right trigger in the right terrain...

Consider using SIMPLE or CHALLENGING TERRAIN with lower angle 38 degree slopes and more supportive shapes and less wind loading exposure.  Avoid Solar aspects and gullies and drainage type features with rocky overhead terrain as 'garbage day' is expected.

Travel advisory:

Monday: Human Triggering is Possible to UN-Likely in the Alpine and improving for Tuesday and Wedensday as a slight cooling and drying  trend develops. 

Outlook:

Generally it will be too warm, with some overnight freezing depending on sky cover and elevation. Freezing levels between 1300m and 2500m with some surface refreezig expected. Monday AM fairly steady rain showers possible.  Winds Light going South through West as it dries into a 'Sunny' day for Wednesday.