Surprising Swan Winds

East winds were stronger than forecast this morning in the Swan Range. We found east aspects stripped and fresh wind slabs on north through southwest aspects at mid elevations as we traveled on a north-south ridge.

• Wind slabs were up to 2 feet deep at the ridge and tapered to only an inch or so 30 to 40 feet down slope. Shooting cracks, recent small natural avalanches, and the little avalanche we triggered were obvious signs to avoid steep westerly slopes. These soft slabs were cracking and sliding on a slick crust below the 8 inches of new snow.
• East winds were blowing snow onto west-facing terrain at upper elevations through about noon, when things calmed down considerably.
• West winds from last night, when snow was falling, looked to have initially loaded the east side of ridges. We saw a few small crowns on those aspects that likely failed overnight and then got stripped as east winds picked up this morning.
• Traveling down-slope of the fresh slabs on westerly slopes we found 6-8 inches of soft snow atop the crust. If winds pick up tomorrow from the west, we could find wind slabs on all aspects in the Swan.
• We saw several moderately sized (D1.5) natural sluffs running on very steep northwest slopes. These ran far and looked like they slid on the same slick crust.
• We found preserved surface hoar 18 inches below the surface on a northeast facing slope. Several tests had mixed results with one ECTP on that layer (hard force). We had to cut through the hard (K) ice crust to test the surface hoar on that slope, so I doubt a human could trigger it there. I would still be concerned about slopes higher than that crust, which we found on all aspects to our high point of about 6400 feet.