ACMG Mountain Conditions Summary for the Rockies and Columbia Mountains. September 20, 2019

Autumn is in full swing in the Rockies and Columbias. Mornings are crisp, afternoons are warm in the sun, the trees are colourful, and if there is precipitation it is generally in the form of snow at higher elevations.

WEATHER
Last weekend was cold and wet with snow in alpine areas in both mountain ranges. Since then it has been variable, running the gamut from sunny to cloudy to showery precipitation.

Similar changeable conditions are forecast for the next week, with some western and northern zones seeing a higher likelihood of showery precipitation than central, southern and eastern areas.

CONDITIONS
Expect varying amounts of snow in the alpine, especially above 3000 m. How much you find will depend aspect, elevation, terrain type, and what region you are in.

With cooler temperatures the rock climbing crags will be slower to dry out after every rain event. Consider what type of climb you are on, corner and crack systems will seep for longer than open faces.

Trails have some muddy sections and will also be slow to dry out, but overall they are in pretty good late season shape.

HAZARDS
Rockfall would be my primary concern on any type of climbing venue.

On alpine routes this risk will increase during the warmer part of the day due to melting snow so early starts are still essential.

On rock climbs seeping crags also spit out more stones. We had a spontaneous rockfall event occur on our climb yesterday - thankfully it was more gravel than anything but it made us mindful of our positioning in the terrain and made us move faster through exposed areas.

Hikers - even some trails are exposed to stonefall so be aware of what is above your head. I always think of this on the Edith-Cory loop and in the Lake O'Hara area.

Small loose snow avalanches can also be expected in the alpine during warming events. I doubt the new snow is masking crevasses much yet, but it is something to begin to consider.

OBJECTIVES
This time of year I think about heading for:

- sunny rock climbs
- shady alpine climbs if there are overhead hazards
- non-technical alpine ridges
- larch hikes!

I avoid:

- climbs in the alpine with technical rock sections
- alpine routes with snow on rock overhead, especially if they are exposed to the sun
- shady rock climbing

Take advantage of the remaining weeks of climbing weather...with careful evaluation there are still lots of things to do!

Mark Klassen
Mountain Guide