Vancouver Island Avalanche Bulletin

Vancouver Island Avalanche Bulletin

PARTY FOR THE BULLETIN! Don’t miss the Vancouver Island Avalanche Bulletin Fund Raising Party 24 January, 2009 at the Riding Fool Hostel in Cumberland. Two great bands, prizes, silent auction items and beer from our friends at Phillp’s Brewing. If you use the bulletin and would like to support it, come on out and party! Call 250 336 2870 or email info@islandalpineguides.com for more info.

Date Issued: Friday, December 26, 2008

Valid Until: Sunday, December 28, 2008

Bulletin Area: This bulletin covers the mountainous region of Vancouver Island from the Mt. Cain Ski Area in the North to the Beaufort range to the South including the mountains of Strathcona Provincial Park.

DANGER RATINGS

Weather: Well just when you thought you were done digging out your drive ways and returning to typical Island life another low pressure spooled up over the pacific and bringing with it a xmas gift for the ski tourer.  Up to 40cms are forecasted for the Island mountains as of Friday morning.  With up to 10-20cms in the Alpine for Friday and another 30  for Saturday we are well into winter.  Freezing levels are expected to remain low with a quick exception on Saturday where a quick jump up to 1600m is expected.  This should be short lived though with the onset of a cold front right behind this warm spike.  Winds will slowly increase today from Mod Westerlies to strong SW winds up to 70-90 kms/hr.

Snowpack: Our Island snowpack is highly variable right now with observations reporting almost no snow at Mt. Cain last weekend to up to 85cms of snow around the Forbidden Plateau area.

Snowpack observations from the Southern end of the reporting region have seen up to 5cms new snow over the last 2 days with reports of isolated pockets of surface hoar up to 5mm sitting on a thin melt freeze crust.  In the Northern areas of the region our new forcasted snow will for the most part be falling onto exposed ground.  Isolated areas of instability were observed last week where a weak facet layer about 10cms thick overlies an old rain crust.  These areas were highly reactive to human triggering with widespread whumphing and propagating cracks. Profiles identified this layer as a problem with very easy results to stability tests. This layer will be highly reactive to the upcoming new snow.  The good news on this layer is that it is isolated to areas of lee loading and should settle itself out with our upcoming additional load.

With up to 30-40cms new snow forecasted with strong SW winds we are in for an increase in our hazard especially in the southern areas of the region with lots of snow available for transport with the strong winds associated.  Start zones will be loading and the large amounts of snow forecasted will be well beyond threshold for avalanche formation. Expect isolated natural avalanche activity on surface hoear pockets and in typical lee features for the forecast period. With the increase in freezing levels and strong winds wind-slabs will form quickly and become reactive to skiing.

In the northern areas most of this new snow will be falling on bare ground with the isolated exceptions mentioned earlier.  The increase in the freezing levels to the north should help the new snow consolodate quickly and make for a good base to buffer us from the rocks and stumps.

Travel advisory: Extra Caution is advised in areas to the south in lee zones and where surface hoar could form such as around lakes and rivers. Stay out of the start zones over the next few days and let this new snow settle out.  With strong winds associated be vigilant for wind-slabs at tree-line also.  All the out of bounds areas at local ski areas are considered tree line elevations.

Extreme caution is advised in areas to the north where this new snow will bury all the rocks and stumps with potentially low density snow that will do little to help protect you from these hazards.  A tree branch through the leg is not a good way to start your season!

Outlook: The storm should abate a bit on Sunday but snowfall is still forecasted but in smaller amounts

Confidence: Fair. weather models are in agreement for timing and duration of precip and wind intensity but were off for the amounts on Friday and Saturday morning. Increased observations now coming in from the field are giving us a good picture of the variability of the snow cover to date.

Are you traveling in the island back country?

Send our forecasters your observations. We are particularly interested in hearing if you have observed avalanche activity or If you or a member of your party has been involved in an avalanche. Email your observations to the Island Alpine Guides Avalanche Bulletin.

Important Notice: This is a regional forecast and significant variation may exist within the forecast area. The information and danger ratings are intended as a trip planning aid for recreational, backcountry users of avalanche terrain; they are not meant to be used as the sole factor in determining the avalanche danger presented by a specific slope. Always include local weather, snowpack and avalanche observations in your decision to travel in avalanche terrain. Observations and experience may lead to different conclusions from what is reported or recommended. See disclaimer for further details. The technical data used to produce these bulletins is obtained from a variety of sources, including local ski areas and remote weather resources.