Matt Zavaglia and his brother attempted to summit Mt. Adams over the holiday weekend, but were turned away just a few hundred feet from the summit due to a lenticular cloud. Those are the wave like clouds seen frequently over Mt. Rainier that look like they just hover, but in fact, feature quite strong winds.
Mountain tops are great for creating these because what happens is you have air that just on the fringe of condensing, but the turbulence from going over the mountains can nudge the air higher to where now it's cold enough to condense into a cloud. The air then sinks a bit and dries out and the cloud ends.
Zavaglia says wind speeds the lenticular cloud he was approaching were sustained 50-80 mph.
He didn't stop to get a picture of that cloud as he was more concerned about surviving the wind blast, but once down to safety, he captured a few others that were firing off over the Cascades:
Meanwhile, Gerald Lammers caught this unique cloud formation over Mt. McDonald south of Port Angeles. These too are likely caused by mountain turbulence:
Have a great weekend!