Avalanche hazard will rise with daytime warming and solar input. Time your day to move off of slopes before they get moist or slushy and steer clear of overhead hazards like cornices.
Summary
Confidence
Weather Forecast
TUESDAY NIGHT: Clearing, light variable wind, alpine low -8 C, freezing level to valley bottom.
WEDNESDAY: Sunny, light to moderate south west wind, alpine high +4 C, freezing level 2300 m.
THURSDAY: Mostly sunny, light to moderate southerly wind, alpine high +7, freezing level 2400 m.
FRIDAY: Increasing cloud, flurries, moderate to strong south west wind, alpine high -1, freezing level 1800 m.
Avalanche Summary
On Monday there were size 1 wet loose avalanches reported in the backcountry near Castle. There were wet loose avalanches size 1-2 from throughout the region out of southerly alpine terrain reported over the weekend.
Snowpack Summary
The alpine may be wind affected in open areas. Snow on all solar aspects and lower elevation bands will start out crusty but may start to get moist by mid morning. Reports suggest snow on northerly terrain above 1600 m has so far remained dry. Cornices are large and looming, and glide cracks are increasing in size...both should be considered unpredictable and given a wide berth.
Around 30 to 60 cm of snow sits above a layer of sugary faceted grains that were buried in mid-February. In some areas, there may be an old layer of feathery surface hoar or facets from late January down 50 to 80 cm deep. There have been no reported avalanches on either of these layers in the region since March 9th in the Crowsnest, but there is always lingering concern that consecutive days in a row of warm temperatures may increase the reactivity of deeper weak layers in isolated areas.
The mid pack is firm and well settled. Some faceted snow and a decomposing melt-freeze crust can be found near the base of the snowpack.
Terrain and Travel
- Be alert to conditions that change with aspect and elevation.
- Avoid sun exposed slopes when the solar radiation is strong, especially if snow is moist or wet
- Avoid steep convexities or areas with a thin, rocky, or variable snowpack.
- Cornices become weak with daytime heating or solar exposure.
Problems
Loose Wet
Sun and warm daytime temperatures can quickly destabilize solar slopes and increase the likelihood of avalanches. Pinwheeling and a moist snow surface are signs that the stability of the upper snowpack is decreasing.
Even small avalanches can be a hazard in high consequence terrain and above terrain traps.
Aspects: South East, South, South West, West.
Elevations: All elevations.
Likelihood
Expected Size
Cornices
Cornices are large and likely weakening with sun and significant daytime heating. Big cornice falls are a hazard on their own but can also trigger avalanches on the slopes below.
Aspects: North, North East, East, West, North West.
Elevations: Alpine.
Likelihood
Expected Size
Valid until: Mar 17th, 2021 4:00PM
