Avalanche Forecast
Issued: Jan 7th, 2015 10:00AM
The alpine rating is , the treeline rating is , and the below treeline rating is Known problems include Loose Wet.
NWAC,
Northwest Avalanche Center
Avoid steep sun exposed slopes if snow becomes wet in more than the top few inches. Smaller loose wet avalanches usually precede large loose wet avalanches.
Summary
Detailed Forecast
Another dry, sunny and warm day is expected Thursday. Freezing levels should be in the 11,000 foot range with light winds. Amazing weather for January.
Loose wet avalanches while unlikely should be the main avalanche problem on Thursday. This may be most likely at higher elevations east of the crest where more of the precipitation will have fallen as snow and less as rain. So the avalanche danger in the above tree line band will be indicated at moderate compared to low in the other areas and bands. Remember that areas with shallow snow may become unstable first or may initiate from rocks or vegetation. Avoid steep sun exposed slopes when snow becomes wet in more than the top few inches.
Snowpack Discussion
East of the crest about 6-12 inches of snowfall Sunday was followed by about 1 to 3 inches of rain on Monday with a warming trend especially Monday. Wow! At higher elevations mainly in the northeast more of the precipitation will have fallen as snow and less as rain before precipitation ended on Monday.
This weather was likely to have produced avalanches east of the crest.
And now sunny unseasonably warm weather is being seen in the Olympics and Cascades mid-week. In most areas this has been causing draining, consolidation, stabiilzing and a resetting of the upper or entire snowpack.
Back country skier Dan Veenhuizen was on Mt Cashmere on Tuesday and noted debris from large avalanches from Sunday and Monday. At 6900 feet he found what should be the December facet layer at about 90 cm below the surface but it was not reactive to an ECT.
Facet layer in a pit on Mt Cashmere on Tuesday by Dan Veenhuizen.
Problems
Loose Wet
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. They generally move slowly, but can contain enough mass to cause significant damage to trees, cars or buildings. 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.
Travel when the snow surface is colder and stronger. Plan your trips to avoid crossing on or under very steep slopes in the afternoon. Move to colder, shadier slopes once the snow surface turns slushly. Avoid steep, sunlit slopes above terrain traps, cliffs areas and long sustained steep pitches.
Several loose wet avalanches, and lots of pinwheels and roller balls.
Loose wet avalanches occur where water is running through the snowpack, and release at or below the trigger point. Avoid terrain traps such as cliffs, gullies, or tree wells. Exit avalanche terrain when you see pinwheels, roller balls, a slushy surface, or during rain-on-snow events.
Aspects: South East, South, South West.
Elevations: All elevations.
Likelihood
Expected Size
Valid until: Jan 8th, 2015 10:00AM
