Avalanche forecast

Banff Yoho Kootenay

May 1 – 2, 2014Parks Canada
View on map
Archived · expired 12 years ago

Avalanche danger

Sat
Sun
Alpine
3 · Considerable
Treeline
4 · High
Below
4 · High
Open full map

Highlights

No expected freeze overnight and rain below 2400m on Friday will keep the hazard elevated until freezing levels drop. SH

Avalanche problems

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely - Very Likely
    Size
    2–3
    This will be most prominent at treeline and below where we expect rain to start  Thursday night into Friday below 2400m.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible - Likely
    Size
    3–4
    With little overnight freeze, the weak basal layer will be susceptible to human triggering in thin areas. Natural activity should slow down over the next 24 hours as the freezing levels slowly go down.

Weather Forecast

Rain starting tonight and freezing levels to 2400m overnight. Alpine temperatures will stay around zero overnight.Expect a mix of rain and snow Friday up to treeline with snow at upper elevations(up to 20cm). No freeze is expected overnight. Models are calling for 30-40cm at upper elevations with  freezing levels lowering by the end of the weekend.

Snowpack Summary

A weak freeze broke down quickly this morning as temperatures rose into the double digits in the alpine early in the day. Thin snowpack areas are isothermal at all elevations and aspects. Basal facets and depth hoar are waking up as the heat penetrated the snowpack.

Avalanche Summary

A widespread natural cycle to size 3.5 has been occurring over the last 24 hours. Lots of loose wet avalanches, and many slides initiating in thin areas and running to ground. One very large avalanche in the Bryant Creek area crossed 3 alpine bowls showing that the weak basal layer is very reactive during these warm conditions.

Confidence

Freezing levels are uncertain

Regions covered