Enjoy the great spring skiing in Jasper - just remember to look for signs of instability related to the daily pattern of afternoon heating that dramatically increases the avalanche hazard. Plan to be off sun exposed slopes early in the day!
Weather Forecast
Cool temperatures and clear skies until Wednesday, promoting good overnight freezes. On Wednesday we expect a significant pulse of precipitation (15mm), accompanied by strong westerly winds in the alpine. This will very likely result in rain below 1600m and up to 30cm of snow at upper elevations. Temps to cool for Thurs, freeze level at 1000m.
Snowpack Summary
Last week's 15cm of storm snow has likely led to some new windslab formation in exposed areas at upper elevations. Spring conditions mean low hazard in AM with frozen snowpack and potentially high hazard with daytime heating. Small loose wet slides are a good indicator that it is time to be heading for apres-ski.
Avalanche Summary
On Friday, several loose avalanches were observed from steep rock cliffs. Alpine and treeline locations were not visible. Steep, Southerly aspects below 1600m are mostly melted out. Watch for daytime heating breaking the crust down increasing the danger. Heating also promotes cornice failures which may initiate a large slide.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Cornices
Cornice Fall is the release of an overhanging mass of snow that forms as the wind moves snow over a sharp terrain feature, such as a ridge, and deposits snow on the downwind (leeward) side. Cornices range in size from small wind drifts of soft snow to large overhangs of hard snow that are 30 feet (10 meters) or taller. They can break off the terrain suddenly and pull back onto the ridge top and catch people by surprise even on the flat ground above the slope. Even small cornices can have enough mass to be destructive and deadly. Cornice Fall can entrain loose surface snow or trigger slab avalanches.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.