_22 JANUARY 1998 _ _SOUTH COAST/VANCOUVER ISLAND_ _WEATHER _On Thursday morning the road summit at Duffey Lake had 3cm overnight with snowline just at the valley floor. Alpine winds are from west and south-west. There is a deep low (960mb) and the satellite image fills the monitor screen. This is approaching from the south-west. It will push right through to the Rockies with warm temperatures and moderate to heavy precipitation on the coast. _SNOWPACK _Thin snowpack areas which have the weak November features do still exist. Where these are around rock and tree islands, convex rolls and terrain irregularities there is a potential for fracture line propogation to connect from those thin areas through areas with deeper snowpack, resulting in large avalanches. On an isolated basis this cycle is being observed in the Interior ranges this week. _AVALANCHES _Size 3 avalanches observed on the north face of Rainbow mountain otherwise mostly size 1 and 2 avalanches reported, natural and with control work. Up the Suskwa valley near Smithers, 8 bombs made 6 avalanches and two were size 3. _DANGER MODERATE _danger on Thursday/Friday but easily going to _CONSIDERABLE _or even _HIGH _danger if the approaching storm is as strong as it looks on the computer image. _TRAVEL ADVISORY _There have been avalanches in the coastal region that run on the November weakness. So far none of these have involved people. Right now the Columbia mountains have a hair trigger condition in isolated terrain that has not avalanched this winter. Think about that while choosing terrain this weekend. _NORTH COLUMBIA_ _WEATHER _Light to moderate precipitation during the week so far, up 5-10mm of rain below 750m and 15-30cm of snow above 1000m. Winds in the alpine have been light to moderate from the south. Temperatures are forecast to go way up, with freezing levels at least to treeline and possibly higher. Rain and snow amounts for the weekend will be slightly less than the coast but snow amounts over 25cm in the higher alpine will be no surprise. _SNOWPACK _Not much change down deeper but new load, warming and alpine winds are all contributing to fair stability at best with a trend to poor over the weekend with approaching storm. Shears are being reported in the storm and recent snow although settlements rates have been reasonable. Fog, low cloud and generally obscured weather have limited alpine snowpack observations. Height of snow in protected lower alpine locations ranges from 200-250cm, close to the 30y average. Watch out for the thin areas. _AVALANCHES _The distribution of the instability described is well shown by two recent skier remote triggered avalanches. One size 3 just west of the Esplanade Range ran 2500m in skiable terrrain. The other was just on the border of north and south Columbia Mountains near Meadow creek. It was size 3.5 and did some impressive logging as it ran. _DANGER HIGH _in the alpine. _TRAVEL ADVISORY "_Skier remote" avalanche trigger means that a skier (or snowmobiler), even from a considerable distance (50-150m is not unusual), causes enough additional stress to the snowpack for an avalanche to start. Woomphing, observed avalanche activity and skier or snowmobiler remote triggers are all obvious indicators of instability. _SOUTH COLUMBIA_ _WEATHER _Temperatures for late January have been pretty warm, at 2000m the maximum has been from -2 to -5degrees in the region with minimums to -7 or -8degrees. New snow on Wednesday/Thursday was from 10-20cm with winds from the south at light strength in the lower alpine terrain. The southerly will continue with warmer, windier and more precipitation forecast for the weekend. This will be even warmer than this week with assistance from a deep low (960mb) pulling up warmer air from Hawaii south. _SNOWPACK _Storm snow from 20-40cm and recent unconsolidated snow are available for wind transport. With moderate to strong winds, additional precipitation (in liquid or solid form) and freezing levels rising to near alpine elevations the stability will quickly become poor over the weekend. Storm snow is settling well but gives some clean shears in field tests. The same tests are not showing much reaction on deeper layers. But it’s still lurking around out there judging from avalanche reported just to the north. Wind effect observed in exposed terrain. _AVALANCHES _I have been watching the reports for the past few days and there has been a slight lull in the level of activity in the south Columbia with the focus for recent events shifting to the north. _DANGER CONSIDERABLE _going to _HIGH _if the weekend warming and precipitation values are as strong as forecast. _TRAVEL ADVISORY _Three things to watch this weekend - how the weather develops, where did those big avalanche release earlier in the winter and, once again, terrain. We the weekend snow travellers, prairie dogs and urban cowboys starved for the mountain freedom must use all the avalanche safety tools to get through the darker part of mid-winter. _ROCKIES_ _WEATHER _Very mild Rockies temperatures from Jasper to Waterton with a slight cooling in Banff on Thursday morning. Range from -3 to -9 degrees at 2000m, down to -11 degrees at 2500m. Light westerly winds and trace to light amounts of snow on higher terrain. The south west flow from the coast is expected to push right through the Rockies with no continental airmass to cool the approach. Moderate snow amounts and milder temperatures for the weekend. _SNOWPACK _The warming has contributed to some rounding of the facets and depth hoar. This has been subtle and slow and contributing to some increase in strength. More noticeable in the pack is there is now reasonable support for skiers and snowmobilers. Finally it is not always trailbreaking through to near ground. Easy compression test in depth hoar near Sunshine. At the Teepee Town profile site there is 118cm and a compression test moderate was observed down 25cm on stellars. In Kananaskis the facet base continues to be a concern._ _ _AVALANCHES _Marmot, Louise and Island lake all had size 1 & 2 avalanches with explosives and ski cutting. _DANGER MODERATE _in the alpine _TRAVEL ADVISORY _Reasonable ski and snowmobile conditions. Ice climbers need to watch the temperature change closely. Warming this weekend will quickly increase the level of danger on ice climbs.