Follow the Bulletin on Twitter and get updates as soon as they are posted!
Traveling in the Backcountry? Send us your observations and become eligible for the Blue Touque "Tip of the Month" prize.
If you have any information about conditions or activity in the back country or If you have observed avalanche activity or been involved in an avalanche, please send your obeservations to us at firstname.lastname@example.org. Each month we'll pick the best contribution to win a prize from the Blue Toque Sport Swap.
Read about the limitations of this avalanche bulletin here.
Confidence: Fair: Watch freezing levels Saturday morning as continued rain would keep the hazard higher.
Note: Friday avalanche problems are listed below. On Saturday & Sunday they simplify to include only thin Windslab and Loose Wet on Solar aspects if there has been 10cm or more of new snow and if the sun comes out.
Past Weather: The Island Alps saw 5 to 10 cm snow Wednesday & Thursday and 30 to 50 mm rain over night Thursday/Friday. Wind was not a factor. Freezing levels rose from 600 m Wednesday and Thursday to a little above Treeline by time of writing.
Main Concerns: (Avalanche problems)
Loose Wet - Rain makes the surface snow unstable. This will effect all elevations and aspects until Saturday and Sunday when only very steep or sunny aspects may slide. Steep terrain and tree bombs will be the first to let go naturally. Any cross slope cutting would produce loose wet slides on terrain steeper than 35 degrees. Avalanches could range in size from only large enough to knock a person over or injure them to large enough to trigger a larger slab. Risk of triggering decreases Saturday AM.
Wet Slab -Persistent Slab - Friday and early Saturday morning only - More rain will add load and weaken existing slabs on all aspects and at all elevations. These slabs may be triggered naturally by rain or other avalanches causing a potential 'step down' avalanche.. Human triggering may be difficult but would produce avalanches from all most large enough to bury, injure or kill a person to more than large enough to bury, injure or kill a person. The persistent crust sliding layer is more than 50 to 100 cm deep in the snowpack.
Cornice - Friday and Saturday morning only- Rain weakens cornices. Cornices are found on West through North to East aspects at Treeline and above. Natural and human triggering is possible. Avalanches could range from small to more than large enough to bury, injure or kill a person, if the falling cornice triggers deeper layers.
Friday - Rain 20 mm. Winds light gusting to moderate from the South. Freezing level 2000m.
Saturday - Rain should change to snow above 1000m, light snow accumulations of 1 to 4 cm. Winds light gusting to moderate from south to South West. Freezing levels 1500m to 2000m dropping in the early morning dropping to below 1000m by end of day.
Sunday - Sunny periods possible with a trace of snow. Winds should be light but rise to 30 KM North to North East and East during the day (West on the West coast). Freezing levels dropping to 300m in the morning and rising to 1000m again during the day.
Avalanche activity - Numerous natural Loose Wet surface avalanches were reported on the East Island, to size 1. No other reports.
A deep coastal snow pack has now undergone dramatic settling, compaction and surface renovations. The surface is loose and wet at the time of writing and it will firm up and freeze by Saturday making the snow much more stable. The 20 February crust is 100 cm down and should become inactive this weekend. Two shears closer to the surface in our last storm snow will compact and bond over night. Watch for breakable crusts and variable surfaces.
Stay out of avalanche terrain in times of high hazard and until the rain stops. Stick to lower angled and/or forested slopes. Stay out from under large slopes. Be aware that wet cornices are suspect and give them a wide berth. Even smaller avalanches can deliver a much heavier load to a slope than a skier; these avalanches could act as possible triggers of a deeper instability as mentioned in the snow pack discussion above.
Breakable crusts, and potential slip and fall hazard may exist over the weekend. Test and re enter the terrain slowly and watch for thin wind slab created by North Easterly winds Sunday.
Prepared by: Niko Weis.
Observations or comments? We want to hear them