Avalanche Forecast

Archived

Jan 2nd, 2020–Jan 3rd, 2020

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Alpine

Natural avalanches possible, human triggered probable.

Treeline

Natural avalanches possible, human triggered probable.

Below Treeline

Natural avalanches unlikely, human triggered possible.

Regions

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Expect a warm, wet, and dangerous day on Friday. Rising temperatures, snow, rain, and strong winds will create hazardous avalanche conditions, particularly at mid and upper elevations. To stay safe conservative terrain choices will be key, avoiding steep slopes until this warmup runs its course.

Discussion

Friday’s avalanche concerns should be limited to the recent snow that overlays a crust formed on New Year’s Day. This crust extends up to 6000 ft in the nearby West North zone and could act as a smooth bed surface for avalanche activity on Friday. In the northern part of the zone and at upper elevations, there could be a foot or more of recent snow during the warm-up phase of the New Year's system, with up to an additional foot of lower density snow falling into the below treeline band after the frontal passage as a convergence zone ended up focusing on the southern parts of the zone.

Timing will play a large roll in any natural avalanche cycle, the avalanche danger, and the avalanche problems. The hazard seems to peak Thursday night into Friday morning as temperatures rise and bring rain to higher elevations in the near treeline band, but with the warm temperature the hazard should linger throughout the day.

Snowpack Discussion

New Regional Synopsis coming soon. We update the Regional Synopsis every Thursday at 6 pm.

Problems

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.