Jasper

Another spring day Sunday ahead of a shift to unsettled weather.

As always in spring, start the day early and finish early.

Keep an eye above - fragile cornices are primed to trigger slabs below.

Moderate

• We are uncertain about forecast precipitation amounts.
• We are uncertain if precipitation will fall as rain or snow.
• We are uncertain due to variable freezing levels.

The warmer temperatures and higher freezing levels are continuing to produce small wet loose avalanches.

Cornices are ripe and fragile. Field teams along the Icefields and the Maligne range have noted cornice failures of which some are triggering slabs on the slopes below.

A size 3 persistent slab was observed this Friday on Sunwapta peak, occurring in the alpine and treeline on a West aspect.

Moist surface snow is present at all elevations on solar aspects. Dry or wind-affected surfaces persist on high north-facing alpine terrain. Sun crusts exist on solar aspects, with multiple melt-freeze crusts below ~2300 m.

The January 24th layer is buried 80–120 cm deep and remains a lingering concern in the alpine. The lower snowpack is generally well consolidated in deeper areas, while shallow areas remain weaker and more faceted.

Some forecasts show up to 8cm of snow overnight on Saturday.

Sunday

A mix of sun and cloud. Alpine temperature: High 1 °C. Ridge wind light to 20 km/h.

Freezing level: 2300 metres.

A mix of sun and cloud with isolated flurries. Alpine temperature: Low -3 °C, High 1 °C. Mostly light ridge wind occasionally gusting to 25 km/h.

Freezing level: 2400 metres.

Flurries up to 9 cm. Alpine temperature: Low -4 °C, High -2 °C. Ridge wind light to 25 km/h.

Freezing level: 2000 metres.

• Start your day early and be out of avalanche terrain during the heat of the day.
• A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
• Use extra caution around cornices: they are large, fragile, and can trigger slabs on slopes below.