Avalanche forecast

Waterton Lakes

Apr 20 – 23, 2014Parks Canada
View on map
Archived · expired 12 years ago

Avalanche danger

Tue
Wed
Alpine
2 · Moderate
Treeline
2 · Moderate
Below
2 · Moderate
Open full map

Highlights

Watch for warm temperatures and potentially some heavy precip this week. Remember, even small amounts of solar heating or rain can weaken snow quickly to cause an increase in the avalanche hazard beyond the posted danger ratings.

Avalanche problems

  • Wind Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Possible
    Size
    1–2
    Isolated  windslabs have developed in open features. These are becoming old however significant transport is still occurring. These may grow or become hidden with incoming snow or weakened with incoming rain.

  • Loose Wet

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Likely
    Size
    1–2
    Even short bursts of solar heating can rapidly affect the snow this time of the year. With mild temperatures in the forecast, watch for rain to affect the snow at lower elevations.

  • Deep Persistent Slabs

    • Alpine
    • Treeline
    • Below treeline
    Likelihood
    Unlikely - Possible
    Size
    2–4
    Solar heating and rain has weakened the upper snowpack BTL. With continued warming, a skier traveling through a thin spot or a large load hitting a slope such as a cornice fall or smaller avalanche could potentially trigger these serious slabs.

Weather Forecast

Watch  for moderate warming on Monday with a freezing level to 2700m and a few showers in the forecast. A poor recovery into Tuesday will allow further shower activity to weaken the snowpack further at lower elevations. Models are conflicted so far for Wednesday but we may see heavy precip. Watch freezing levels and precip amounts carefully.

Snowpack Summary

10 to 40 cm of snow now lies on the April 11 crust that is found on N aspects to 2300m and to ridgelines on solar aspects. Moist snow below 1800m on all aspects. The deeply buried February Facets and early season Basal Facets remain weak and will likely wake up with significant and sustained heating.

Avalanche Summary

Widespread Loose Wet activity has been seen with rain soaked snow below 2000m. These events have been up to size 1.5 running 10 to 20 cm deep over the April 11 crust on all aspects below about 2200m.

Confidence

Timing, track, or intensity of incoming weather system is uncertain on Wednesday

Regions covered