Synoptic-Scale Environments Associated with High Plains Severe Thunderstorms

Abstract

Typical synoptic-scale features are described for summertime severe thunderstorms on the High Plains. Severe weather generally occurs on several days in succession, under conditions that are relatively benign in terms of conventional severe weather parameters. Low-level conditions strongly resemble previously described convective flash flood situations. Moderate westerly flow is indicated at mid- and upper-levels, with the jet stream axis typically across or north of the threat area. Preexisting mesoscale systems often play a significant role in organizing the activity. Examples are shown, including one involving a thunderstorm outflow boundary.