The official start to summer has many places in the Rockies and Columbia's under a thunderstorm watch as unsettled showery weather rolls in for the next couple days. Sunday looks drier, with more unsettled weather Monday before things improve. Keep a close eye on the sky for afternoon thunderstorm development and bring what you need for a quick retreat if necessary.
Junuary on the coast has ended. Some intense the past couple of days has resulted in isothermal snow conditions in the alpine, poor freezes, and a slab avalanche cycle within recent (last week) and old snow layers up to Size 3. Several guides have turned around on common objectives in the Sea to Sky corridor for this reason along with the threat of falling cornices.
Many alpine rock objectives have now come into shape, with good conditions being reported in areas such as the Tantalus Range.
The fabulous spring mountain conditions have been interrupted by the snow, rain and wind of the past week. In Glacier Park, reports of up to 50cm of new snow having fallen above treeline over the past few days. Similar amounts in the Nakusp region at treeline and I would suspect that is representative of conditions throughout most of the Columbia mtns alpine.
The weather on the coast has been unsettled since last weekend, with 30-40cm of new snow accumulated in the alpine on Blackcomb Mountain. The new snow was wet and sluffing today, as you would expect this time of year. No slab avalanche activity has been reported, although it is possible with that much new snow. The new snow fell as rain below treeline, which has helped to melt away last winters snow lingering on the trails.
It's been a great week for being up high in the mountains of Interior BC and the Rockies. Alpine routes in Rogers Pass have been getting traffic including shadier mid-elevation routes like MacDonald NW ridge. Mixed routes in the Rockies have been in good condition with great overnight freezes and easy travel on settled spring snow. Glacier coverage continues to make for generally uncomplicated travel, although as always at this time of the year caution is required in the way of roping up and monitoring snow depth vigilantly with a probe.
Conditions are currently suitable for both alpine climbing and skiing in the Coast Mountains, although you have to do your research and pick your objectives carefully to find out where the snow still remains. You can still expect to run into significant snow patches as low as 1300m (depending on aspect, tree cover and sun exposure), then continuous snow before you reach the alpine.
Continued warm weather this week put the brakes on all but the more serious efforts at getting out on skis. Exceptions were the high peaks, such as Mounts Columbia, Andromeda and Kitchener in the Rockies which have been seeing a fair bit of traffic. Casual outings are hindered by dry or isothermal slopes into the treeline elevations, although there is the standard May traffic at Parker's Ridge which has high road access at almost 2200 m.
Reports of surprisingly large treeline elevation slab avalanches were reported earlier in the week along the Icefield Parkway in Banff.
No really dramatic changes reported over the past week but the snowline continues to rise as do the rivers and the tick populations.
Forecast looks like a nice warm sunny weekend for the whole region. Still some corn snow skiing to be had but some walking will probably be required except along the Icefields parkway and some spots at Rogers Pass. Clear nights, early starts and careful terrain inspection and selection will be the key to getting some good safe turns in. In some ways unconsolidated moist snow at low elevations could be the biggest ski injury hazard.
This is the first Mountain Conditions Summary for 2018. Spring has finally arrived with some warm temperatures and lots of snowmelt below treeline. It is still winter/spring in most areas at Treeline and the Alpine and snow will remain above 2200m for a long while yet close to the Rockies and Columbia divides.
This past week's little storms left most their load west of the divide. Avalanche hazard has risen and in much of the Columbia Mountains it is now Considerable hazard in the alpine, potentially rising to High with the next storm by Sunday. If the forecast strong SW winds come to the Rockies the avalanche hazard will spike there too as wind slabs build mass. As we all know, Considerable hazard is when the accidents seem to happen most, and as Steve mentioned last week this is about the right time of the year for the first avalanche incident -- so don't let it happen to you this weekend.