Storm Slabs
- Alpine
- Treeline
- Below treeline
- Likelihood
- Possible - Likely
- Size
- 1–2
At upper elevations, where precipitation has fallen as new snow, storm slabs may form. Especially on lee aspects, where wind has redistributed the new snow.
Loose wet avalanches remain possible as the new snow adapts to heavy rain. If you find dry snow in the alpine, be cautions of reactive storm slabs, especially on wind -loaded features.
At upper elevations, where precipitation has fallen as new snow, storm slabs may form. Especially on lee aspects, where wind has redistributed the new snow.
Where the snowpack is rain-soaked, expect loose wet avalanches to be likely.
On Sunday, multiple small (size 1) loose wet avalanches at tree line were observed near Mt Washington on all aspects. Observations are limited at this time, but we suspect a widespread avalanche cycle has occurred over the last 48 hrs.
30 to 50 cm of new snow has been saturated by heavy rain. Except the upper alpine, where rain may have fallen as new snow. A thick crust is buried beneath the new snow.
The mid and lower snowpack is generally moist and well-settled, with average depths of 120–170 cm at treeline.
Monday Night
Cloudy. 10 to 25 mm of rain at treeline. 60 km/h southwest ridgetop wind. Treeline temperature 6 °C. Freezing level 2800 m.
Tuesday
Mostly cloudy. 1 mm of rain at treeline. 40 km/h southwest ridgetop wind. Treeline temperature 6 °C. Freezing level 3400 m.
Mix of sun and clouds. 1 to 3 mm of rain at treeline. 40 km/h west ridgetop wind. Treeline temperature 5 °C. Freezing level 2700 m.
ThursdayMostly sunny. 10 km/h north ridgetop wind. Treeline temperature 6 °C. Freezing level 3200 m.
More details can be found in the Mountain Weather Forecast.