The scumbags pulled out all the stops to spray the crap out of Chiloquin, OR, 8-26-16.
The sky was filled with start-stop expanding wispy trails, despite the relative humidity being between 10 and 16 percent at cruising altitude. Contrails cannot form and persist (in the absence of condensation nuclei) unless the air is supersaturated. Today it was dry as a bone. Here’s a link to the Wyoming Soundings and the Wikipedia definition of condensation.