Avalanche Forecast
Regions: Mt Hood.
The avalanche danger should increase less at Mt Hood on Friday than in the Washington Cascades. But be sure to watch for loose wet or wet slab conditions.
Detailed Forecast
West flow and an atmospheric river (aka the Pineapple Express) of warm front moisture will begin moving over the upper ridge and to the Northwest on Friday. Rain or snow should become moderate to heavy mainly in the Olympics and north to central Cascades by Friday afternoon and continue Friday night with rising snow levels.
In all areas west of the crest loose wet and and wet slab avalanches will be listed at the avalanche problems on Friday. These problems are more likely in areas of the Washington Cascades with the most recent snowfall and expected greater rainfall on Friday.
Often loose wet avalanches occur just prior to wet slab avalanches. Avoid steep slopes if you are in increasing heavy rain and start to see wet snow deeper than a few inches or increasing natural pinwheels or rollerballs.
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Snowpack Discussion
Snow on the back end of the last storm Sunday and Monday was only in the 5-6 inch range at Mt Hood.
NWAC pro-observer CJ Svela was at Timberline on Sunday and reported new snow over a breakable crust. Rounded grain and melt form layers in the mid pack seemed to lack consistent shears and tests did not indicate propagation.
The Meadows patrol reported crusts and melt forms in the upper pack on Wednesday with good stability. Some cool snow from the last storm was seen on N-NE slopes.
The mid and lower snowpack at Mt Hood should also mainly consist of crusts and stabilized rounded grain or melt form layers from warm  periods so far this winter.
A weak dissipating front is moving across the Olympics and Cascades on Thursday. Snow and rain amounts are expected to be light and not have a great effect on snow conditions.
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: All aspects.
Elevations: All elevations.
Likelihood: Possible
Expected Size: 1 - 1
Wet Slabs
Release of a cohesive layer of snow (a slab) that is generally moist or wet when the flow of liquid water weakens the bond between the slab and the surface below (snow or ground). They often occur during prolonged warming events and/or rain-on-snow events. Wet Slab avalanches can be very destructive.
Avoid terrain where and when you suspect Wet Slab avalanche activity. Give yourself a wide safety buffer to handle the uncertainty
A Wet Slab avalanche. In this avalanche, the meltwater pooled above a dusty layer of snow. Note all the smaller wet loose avalanches to either side.
Wet slabs occur when there is liquid water in the snowpack, and can release during the first few days of a warming period. Travel early in the day and avoiding avalanche paths when you see pinwheels, roller balls, loose wet avalanches, and during rain-on-snow events.
Likelihood: Unlikely
Expected Size: 1 - 1