Dashboard Regions Weather Stations Radar Alerts Glossary
Contact About
Log In

Register for an account and never miss a forecast again!

Register

Avalanche Forecast

Archived

Mar 27th, 2015–Mar 28th, 2015

Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.
Alpine
Natural avalanches unlikely, human triggered possible.
Treeline
Natural avalanches unlikely, human triggered possible.
Below Treeline
Natural avalanches unlikely.

Regions

.

Use caution in higher elevations where possibly greater new snow may accumulate, especially lee slopes near ridges. Watch for areas of wet snow at mid elevations, and during daytime warming. 

Detailed Forecast

 

A frontal passage Friday night should cause some light new snow, but initially rain changing to snow should leave good bonding of new snow to the old wet snow surface. 

Watch for areas where new snow has been transported by wind to lee slopes at higher elevations along ridges. Also, watch for cornice development that may be soft and sensitive to trigger or release from daytime warming.

Less recent snow and ample terrain anchors may limit the avalanche danger below treeline. Many areas at the lowest elevations do not have enough snow to cause an avalanche danger.

Snowpack Discussion

The 1-2 feet of snow that fell in mid-march, mainly in the northeast Cascades, has settled or melted and likely been absorbed into the upper snowpack. 

The DOT crew working at Washington Pass on Monday and Tuesday reports mostly stable overall snow conditions with 4-6 inches of recent snow above the pass and about 2 inches at pass level. One natural loose dry avalanche was seen at about 6500 feet on Silver Star Peak on Tuesday.

Only light amounts of rain and snow fell Wednesday along with a gradual warming trend along the east slopes. 

Sunshine and very warm temperatures Thursday and again Friday have likely created significant surface snow melt, leading to consolidated melt-freeze conditions. 

Snowdepths vary greatly across the east slopes with a regionally healthy snowpack in the northeast Cascades to bare solar and lower elevation slopes in the central and southeast Cascades.

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.