Abstract
Satellite imagery dramatically portrays a mesoscale organization of deep convection over the south central United States on 5 June 1986. Free convection was expected over the region. The rapid development and organization of the convection simultaneously across a broad area suggests the presence of a mesoscale instability. Analysis of satellite and conventional data suggests that a layer of weak symmetric stability modified the atmosphere's response to free convective instability, contributing to the highly organized banded structure observed.