Roger's SkyPix

Gallery of Outflow

Double Decker with Pileus

Double Decker with Pileus

Wyoming weather can change ever so fast. Less than an hour before, only a few high based, fuzzy and amorphous looking showers, with terrible definition, littered the sky under a canopy of high clouds produced by separate storms in the Bighorn Mountains. After heading east from Buffalo to Gillette, we turned around to be greeted by a western sky painted slate, cyan and turquoise by a spectacularly laminated wall of thunderstorms. For just a small moment, two thin lenses of pileus formed above the upper deck of the shelf, adding another dollop of banded texture to an already beautiful stormscape. Pileus forms as stratified layers of high humidity condense fast, usually when suddenly shoved upward by deep, intense convective towers. The towers soon blast right up through the pileus, destroying it. In this case, the deepening slab of lift above the gust front, with a little help from an attached clump of shallower convection, hoisted the humid layers lying above just enough to create the formations.

3 W Gillette WY (16 Jun 7) Looking NW