Avalanche Forecast

Issued: Mar 30th, 2014 9:46AM

The alpine rating is considerable, the treeline rating is moderate, and the below treeline rating is moderate. Known problems include Storm Slabs and Deep Persistent Slabs.

ghelgeson, Avalanche Canada

South Coast.

Summary

Confidence

Fair - Timing or intensity of solar radiation is uncertain on Tuesday

Weather Forecast

Synopsis: The trough that delivered snow through the weekend is starting to weaken, giving way to sunny skies and seasonably cool temperatures.Monday: Freezing Level: 1300 - 1600m; Precipitation: Nil; Wind: Treeline: Light, E | Ridgetop: Light, SETuesday: Freezing Level: 1400 - 1700m; Precipitation: Nil; Wind: Treeline: Light, Variable | Ridgetop: Light, NWWednesday: Freezing Level: 1300m - 1500m; Precipitation: Trace; Wind: Treeline: Light, W | Ridgetop: Light, W

Avalanche Summary

Avalanche activity in the northern portion of the region was limited to natural wet surface sluffs out of steep terrain below treeline. On the Coquihalla a few loose moist avalanches initiated in rock slab start zones ran to size 2.5, terminating in the bottom of the runouts.

Snowpack Summary

The storm produced 10 - 25 cm in the north and around 10 cm in the south. Light to moderate winds generally out of the south formed sensitive wind slabs on isolated terrain features at and above treeline. Below 2000m the new snow rests on a thin melt freeze crust on all aspects, with the exception being north facing terrain features above 1500m. The persistent weak layers from early March and early February continue to be a concern. The March weak layer of wind-scoured crusts, melt-freeze crusts, and/or surface hoar is reported to be down 60 - 100cm. The February crust/facet/surface hoar layer is now deeply buried down 150 - 250cm and may still be triggered by heavy loads like cornice falls or storm slab avalanches in motion. Long fracture propagations resulting in very large avalanches are possible with this layer. Avalanches releasing on these layers may step down to the ground during periods of strong solar radiation or warm spring rain.

Problems

Storm Slabs

Cool temps and mostly cloudy skies should help this interface to settle out, but remain vigilant for potentially sensitive wind slabs immediately lee of ridge crest. Direct sun and warming temps could initiate natural activity.

Avoid exposure to terrain traps where the consequences of a small avalanche could be serious.>The new snow will likely require another day to settle and stabilize.>Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet.>Use ridges or ribs to avoid pockets of wind loaded snow.>

Aspects: All aspects.

Elevations: All elevations.

Likelihood

Possible - Likely

Expected Size

1 - 4

Deep Persistent Slabs

Two deep weak layers exist in the snowpack. These weak layers could be activated by cornice fall, a surface avalanche in motion, or a rider finding the sweet spot, likely near a rock outcropping, or anywhere the snowpack goes from thick to thin.

Be aware of the potential for large, deep avalanches due to the presence of buried facets and surface hoar.>Extra caution needed around cornices with current conditions.>Be aware of thin areas that may propogate to deeper instabilites.>

Aspects: All aspects.

Elevations: Alpine, Treeline.

Likelihood

Unlikely - Possible

Expected Size

3 - 6

Valid until: Mar 31st, 2014 2:00PM