Avalanche Forecast
Issued: Mar 27th, 2015 8:00AM
The alpine rating is Persistent Slabs and Loose Wet.
, the treeline rating is , and the below treeline rating is Known problems includeFreezing levels are expected to climb to 2900m today. Warm temperatures will weaken the snowpack and increase avalanche hazard at all elevations.
Summary
Weather Forecast
Cloudy and dry conditions today with a stationary warm air mass over the area. Freezing levels are expected to climb to 2900m this afternoon. Precipitation begins this evening with 6mm of rain for the overnight period. Daytime temperatures remain warm over the weekend with modest cooling at night and strong SW winds. 14 cm of snow for Sunday.
Snowpack Summary
Overnight winds have created wind slabs on high elevation northerly aspects. Warm temperatures prevented an overnight re-freeze leading to moist surface snow below 2100m. Above TL, up to 70cm of snow sits over several persistent week layers in the form of crusts, surface hoar and facetted layers which are reactive to light loads such as skiers.
Avalanche Summary
Yesterday a field team on Mt Abbott observed several loose snow avalanches up to size 2.0, running in steep alpine terrain during the warmest part of the day. Two size 2.0 moist avalanches were observed in the highway corridor running on Mt MacDonald, on the east side of Rogers Pass.
Confidence
Freezing levels are uncertain
Problems
Persistent Slabs
Layers down 50-100cm have been triggered recently by light loads such as skiers and sluffing from steep terrain. Remote triggering and wide propagations are possible. Cornice failures from warm daytime temperatures could trigger these layers.
Avoid exposure to overhead avalanche terrain, large avalanches may reach the end of run out zones.Be aware of the potential for wide propagations.
Aspects: All aspects.
Elevations: Alpine, Treeline.
Likelihood
Expected Size
Loose Wet
Warm overnight temperatures prevented a re-freeze of moist surface snow. Freezing levels will climb to 2900m in Rogers Pass with an alpine high of 5 C. Warm temperatures will quickly weaken the snowpack making loose snow avalanches very likely.
Watch for clues, like sluffing off of cliffs, that the snowpack is warming up.
Aspects: All aspects.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Mar 28th, 2015 8:00AM