JANUARY 30, 1997 SOUTH COAST & VANCOUVER ISLAND WEATHER: A warm winter storm is in effect and combined values of precipitation, strong westerly winds and freezing levels going up to 2500m will contribute to a high level of avalanche danger. The observations are based on information from Wednesday night when the heaviest precipitation was starting. Twelve hour snowfall overnight to Thursday morning was 40cm above 1700m in the Garibaldi area with rain below 1500m. Winds at ridge top to 120kph from the west. Temperatures are forecast to cool by the weekend. SNOWPACK: Rain soaked snowpack at lower elevations and up to 1500m. Storm snow load has very poor stability and is running naturally. The deeper snowpack is generally quite strong with only isolated areas that will still react to the 11 November surface. AVALANCHES: Lots of avalanches, large naturals closing roads and running in areas that receive intense control during the winter. Few observations at backcountry locations due to poor visibility and no flying by helicopter ski operations. DANGER: HIGH to EXTREME danger while the storm continues. This may reduce to CONSIDERABLE twenty four hours after the storm with some cooling and easing of the winds. TRAVEL ADVISORY: Step out carefully when the storm breaks. During times of HIGH danger, natural and human triggered avalanches are likely. Travel in avalanche terrain is not recommended. BULLETIN SPONSORED BY: THE NORTH FACE NORTH COLUMBIA WEATHER: Some elements of the storm do not appear to have reached their peak. Precipitation amounts have been snow at all elevations to Thursday morning with a chance of rain below 1000m before it ends. In Revelstoke since Tuesday there has been 45cm of snow. Strong westerly winds in the alpine have created large dense slabs as the temperatures get warmer. Watch out for the inversion which is getting eroded quickly. SNOWPACK: Foot and ski penetration is in the range of 1 metre to 50cm respectively in undisturbed snow just below treeline. The storm snow has poor stability and sluffs easily on steep treed terrain. In the alpine there have been few observations in the past 36hours due to poor visibility and high avalanche danger. Snow mushrooms on trees also have poor stability. The two recent surface hoar layers and the 11 November crust are the principal slide boundaries. Way further north, in the southern Skeena Mountains observers are reporting the warming with rain to middle mountain elevations is causing a poor stability snowpack. AVALANCHES: Many large avalanches size 3 and 3.5 running naturally, some observed on be running on the 11 November layer and running long distances, up to 2km with 3.5km long fracture lines. DANGER: HIGH danger going to EXTREME if the freezing level goes, as forecast, to 1700metres. TRAVEL ADVISORY: EXTREME avalanche danger means "widespread natural or human triggered avalanches are certain". Extreme is the highest level of danger and this is the first time this condition has occurred this winter. The danger will drop if cooling occurs and after the storm passes. JANUARY 30, 1997 30 January 1997 SOUTH COLUMBIA WEATHER: The same weather system for the coast and north Columbia is warming this region too. All areas from the US border to the Bugaboos have warmed with the freezing level going to nearly 2000m. Winds over 100kmh from the west and overnight precipitation from 20-30mm of water equivalent. There may be some cooling before the next system rolls in over the weekend. SNOWPACK: There is an obvious storm instability snowpack. There were limited alpine observations but classic contributory factors to a poor stability snowpack are all there. The easy shears were already identified and all it needed was new load and warming to get everything moving. The two recent surface hoar layers will shear easily and with adequate propagation avalanche may release down to the 11 November crust. Around all the Columbia mountains the 11 November has had most erratic performance. One day it goes big near Valemount, the next day near Galena and then over to the Adamants, jumping all over. Maybe after this storm it will get very isolated. But the weakness is increasingly deep and that crust went up to nearly 3000metres in some places. AVALANCHES: Large natural avalanches on the Kootenay Pass highway up to 5m deep. Many back country avalanches running naturally. DANGER: HIGH danger going to EXTREME if forecast weather prevails with the next storm load over the weekend. TRAVEL ADVISORY: This is the first time this winter that an Extreme avalanche danger warning has been issued. Travel in avalanche terrain should be avoided and stay on low angle terrain well away from avalanche slopes. Main trails in low angle terrain for snowmobiling and the ski areas have safe conditions. BULLETIN SPONSORED BY: THE NORTH FACE 30 January 1997 ROCKIES WEATHER: Finally, the weather and snowpack conditions that may contribute to a widespread cycle of avalanches throughout the region have arrived. Freezing rain during Wednesday night in Jasper Park. Warming temperatures, strong westerly winds and moderate snow amounts are forecast. The Chinook in the east and advancing westerly go hand in hand but the total warming looks set to meet on the Continental Divide. SNOWPACK: A Rockies snowpack with nearly all its traditional characteristics is available for complete collapse in the right place at the right time. Thin snowpack areas are nearly completely faceted snowpack with hard slab on top and large depth hoar at the base. Areas of deeper snowpack have a generally stronger mid and base pack but the 11 November crust with facets is still a feature most recently reported in Marmot. The more recent surface hoar layers are already reactive with wind loading and temperature change. AVALANCHES: Small slab releases already running naturally are sometimes pulling out to deeper layers. One avalanche ran near Marmot that had not been observed for many years. Avalanches reported on Wednesday were mostly size 1.5 but avalanche control with explosives is being done while this Bulletin is prepared. DANGER: HIGH TRAVEL ADVISORY: After getting out of the grip of the Continental icebox we get instant high avalanche danger. Ice climbing on routes that have any exposure to avalanche terrain above are specially dangerous. But the snowmobile and ski season is early and the best conditions are often in April.