This is the last regular bulletin of the season for Glacier Park. Bulletins will be updated periodically as conditions change. Springtime conditions can change rapidly, from hot and sunny to snowy and cold. Be aware of changing danger levels.
Weather Forecast
A mix of sun and cloud will dominate for the last week of April and beginning of May. Typical springtime patterns of sunny breaks, combined with convective snow flurries means you should plan for anything. A ridge of high pressure is expected for the end of the week. Freezing levels will range from 1300 m to as high as 2600 m by the weekend.
Snowpack Summary
Springtime conditions: snow flurries continue to deposit new snow in the alpine and treeline, with freezing levels near 1300m. Moderate to strong winds continue to create hard and soft slabs in wind exposed areas. Much of the snowpack is isothermal - freezing overnight, and becoming soft whenever the sun pokes out. Cornices are large.
Avalanche Summary
Deep large avalanches are are still possible. On April 29, a near neighbor reported a size 3.5 on a SE aspect. Few details given, but this likely failed on a deep PWL. In Glacier Park, moist storm snow avalanches continue to be noted at lower elevations. Glide cracks appear stagnant for the moment, but should be treated with caution.
Confidence
Timing, track, or intensity of incoming weather system is uncertain
Problems
Wind Slabs
Wind Slab avalanches are the release of a cohesive layer of snow (a slab) formed by the wind. Wind typically transports snow from the upwind sides of terrain features and deposits snow on the downwind side. Wind slabs are often smooth and rounded and sometimes sound hollow, and can range from soft to hard. Wind slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Storm Slabs
Storm Slab avalanches are the release of a cohesive layer (a slab) of new snow that breaks within new snow or on the old snow surface. Storm-slabs typically last between a few hours and few days (following snowfall). Storm-slabs that form over a persistent weak layer (surface hoar, depth hoar, or near-surface facets) may be termed Persistent Slabs or may develop into Persistent Slabs.
Loose Wet
Loose Wet avalanches are the release of wet unconsolidated snow or slush. These avalanches typically occur within layers of wet snow near the surface of the snowpack, but they may quickly gouge into lower snowpack layers. Like Loose Dry Avalanches, they start at a point and entrain snow as they move downhill, forming a fan-shaped avalanche. Other names for loose-wet avalanches include point-release avalanches or sluffs. Loose Wet avalanches can trigger slab avalanches that break into deeper snow layers.