Kurt, your geography sucks
"Yup, Seattle weather sucks. Rains all the time. This. however, is slightly unusual."
For those without the benefit of (or wherewithal to use) google or mapquest, Manson is 300 km east of Seattle, over a mountain range, at the edge of a high desert plain. Definitely not pacific maritime/Seattle climes.
Most travellers in the area are accustomed to "danger: falling rocks" signs, which I hope will be humorously vandalized to commemorate this event.