Archived forecast for Sunday, March 10, 2024

This is archived in relation to a fatality on 3/10 on or near Pump Peak. The avalanche.ca archives are a bit awkward with flexible regions and the result from clicking on the map can differ from that obtained by the location search. We have tried to get the best result by first using the map and then the location search in that area. We believe the advisory here was in effect for Pump Peak on 3/10.

They also date advisories by the ending date so this was listed as 3/11 but expired at 0400 that day.


Date Issued: Sunday, March 10, 2024 at 04:00
Valid Until: Monday, March 11, 2024 at 04:00
Prepared by: jpercival

Ongoing stormy weather will continue to deliver heavy snow, strong winds, and warming temperatures. Plan to seek non avalanche terrain, free from overhead hazard.

Danger Ratings
Sunday
Alpine: 4 - High
Treeline: 4 - High
Below Treeline: 4 - High

Terrain and Travel Advice

    Avoid all avalanche terrain during periods of heavy snowfall.
    Avoid all avalanche terrain during periods of heavy loading from new snow, wind, or rain.
    Make conservative terrain choices and avoid overhead hazard.
    Be especially cautious as you transition into wind affected terrain.

Problems

Avalanche Problem 1: Storm slab
What Elevation? - Below treeline, Treeline, Alpine
Which Slopes? - North, Northeast, East, Southeast, south, Southwest, West, Northwest
Chances of Avalanches? - Very likely
Expected Size? - Small - Large

A new and building storm slab is forming over a variety of surfaces. Watch for deeper and more reactive slabs near ridgelines on north aspect terrain.

Avalanche Summary

On Friday, numerous small (size 1) easily triggered storm slabs have been observed and reported. 

Snowpack Summary

New snowfall amounts over the weekend are forecast to be in excess of 100 cm and this new snow will overlie a variety of mostly cold and hard surfaces and in protected areas surface hoar. Expect strong southwest winds to strip snow from ridgelines and exposed features and deposit new snow into deep pockets in lee aspect terrain.

Below this, over 100 cm of old storm snow appears to be settling and bonding well to the widespread crust below it. Below this crust, 40-70 cm of previous storm snow in some areas sits on a strengthening layer of pellet-like graupel over an earlier crust.

The lower snowpack is well consolidated.

Weather Summary

Saturday night

Cloudy with heavy snowfall bringing 30-50 cm of new snow. 50-80 km/h southwest alpine wind. Treeline temperature around -2 °C with freezing levels around 1200 m.

Sunday

Cloudy with continuing heavy snowfall bringing 30-50 cm of new snow and 2-day totals of 100-150 cm. 20-40 km/h southwest alpine wind. Treeline temperature -4°C with freezing level around 1000 m

Confidence: Moderate, Uncertainty is due to the timing of the incoming weather system. Forecast precipitation (either snow or rain) amounts are uncertain.