North Rockies

Reactive wind slabs may exist at upper elevations, especially on north through east facing terrain.

Watch for signs of instability like whumpfing or cracking beneath your feet.

On Tuesday, a natural wet loose avalanche was reported (size 2) from a northeast aspect in the alpine. The report indicated that the avalanche was several days old.

Reactive wind slabs may exist with new snow and moderate southwest winds, especially on north aspects in the alpine. Lower elevations may see wet loose and wet slab avalanche activity with rising freezing levels.

Up to 20 cm exists at treeline and above. North aspects above 2200 m are holding dry snow. A surface crust has formed on all aspects at treeline and on solar aspect in the alpine. Below treeline is isothermal snow. This crust is likely to soften with rising freezing levels.

Below this, a 5 to 25 cm crust from last week's rain event is present. This is capping a moist upper snowpack.

A persistent weak layer from early March, 40 to 80 cm deep, most likely exists as surface hoar on sheltered north and east aspects in the alpine. Its distribution is variable, and there have been no substantial reports of recent avalanches, but it should still be considered when evaluating slopes.

Wednesday Night

Mostly clear with some cloud and flurries up to 5 cm. 20 to 50 km/h southwest ridgetop wind. Treeline temperature -3 °C. Freezing level falling to valley bottom.

Thursday

Cloudy with snow starting in the afternoon up to 10 cm. 50 to 70 km/h southwest ridgetop wind. Treeline temperature 0 °C. Freezing level 2000 m. Freezing level dropping to valley bottom.

Friday

Cloudy with flurries 5 to 25 cm. 25 to 70 km/h west ridgetop wind. Treeline temperature -3 °C. Freezing level 1500 m.

Saturday

Mix of sun and cloud with isolated flurries up to 5 cm. 25 gusting to 45 km/h northwest ridgetop wind. Treeline temperature -3 °C. Freezing level 1200 m.

More details can be found in the Mountain Weather Forecast.

• Be careful with wind-loaded pockets, especially near ridge crests and rollovers.
• A moist or wet snow surface, pinwheeling, and natural avalanches are all indicators of a weakening snowpack.
• Avalanche activity is unlikely when a thick melt-freeze crust is present on the snow surface.