Last Tuesday, August 6th, folks around Seattle were enjoying another beautiful, sunny, warm day. However, there were a few unique clouds that interrupted that peaceful day, and had locals wondering what on Earth might be in the sky. "Jellyfish" clouds, as they are sometimes referred to because of their shape, made a rare appearance in Washington. Their technical term is actually "Fall Streaks", which are a form of virga.
Virga, is rain from a cloud, but that rain never actually makes it to the ground because it evaporates too quickly. Fall streaks are similar, but instead of being in the form of rain, they are ice crystals. As those ice crystals "fall" from the cloud they change directly from a solid to a gas state, or sublimination.
Notice in the first picture below that there is one line of "jellyfish" clouds in the western section of the state near Seattle, and another in the eastern section of the state.