Basin & Range Atmosphere

Yesterday, the rolling farmlands of Ohio's Glaciated Plain were bathed in sunshine.  As we approached the Indiana line, however, a range of vapor stretched across the western horizon, its upper peaks gleaming in the bright morning sun.

Cutting through this wall, a torrent of rain drenched the car but we soon emerged into calm sunshine on its western edge.  There we saw other ranges to our north, south and west, all trending southwest to northeast and separated by pale blue skies.  This atmosphere of banded storms, rising ahead of a strong cold front, was reminiscent of the Basin and Range Province of the American West, where fault block ranges poke above the high desert.

While the Basin & Range topography was produced by tectonic forces from below (a process that continues today), yesterday's Midwestern scene resulted from turbulence above Earth's surface.  Ahead of the cold front, southwesterly winds pushed warm, humid air toward the Great Lakes and low pressure along the front provided lift, igniting bands of thunderstorms.