Avalanche Forecast
Regions: Mt Hood.
The avalanche danger is expected to be limited for most of daylight hours on Thursday. Change your plans if the next system arrives sooner than expected and you see significant layers of new snow starting to build at higher elevations or significant wet snow deeper than boot top at lower elevations.
Detailed Forecast
A relative break between systems with little change in snow levels and temperatures should be seen most of the daylight hours on Thursday.
Continue to watch for loose wet avalanche potential above terrain traps such as above cliffs, near gullies or where avalanche debris would deeply accumulate. These are the types of places that even small wet avalanches can have serious unintended consequences.
Rain and snow from a warm front should start to move into the Northwest Thursday late afternoon. Be prepared to change your plans if this system arrives sooner than expected and you see significant layers of new snow starting to build at higher elevations or significant wet snow deeper than boot top at lower elevations.
Snowpack Discussion
Weather and Snowpack
A large upper ridge and warm air mass aloft has been over the US west coast the past 3 days. Temperatures at NWAC stations at Mt Hood have ranged in the 40 to 50 degree F range the past couple days which is the warmest weather so far this season. The very warm temperatures and solar effects caused loose wet avalanches, consolidation and night-to-morning surface crusts. This will have further stabilized the lower and mid snow pack and turned recent storm snow into moist to wet snow in most areas.
An initial weak front is moving over the Northwest today. Most areas should see a little light rain with a lowering of high snow levels. This should not greatly change snow conditions.
Recent Observations
Limited loose wet snow conditions were seen by Tuesday at Mt Hood by the pro-patrol. Moderate winds limited surface snow melt near and above treeline. More significant wet snow conditions were seen below treeline but limited or no loose wet avalanches. Â
Avalanche 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: Possible
Expected Size: 1 - 1