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Historical Temperature Rankings by State: July 1993

The summer of 1993 was unseasonably cold over much of the mountain west with drought conditions throughout the southeast. These weather conditions were caused by two stationary pressure systems located over the continental United States at that time. About the second week of June, a large "dome" of high pressure in the upper atmosphere became nearly stationary over the southeastern United States while at about the same time an unusally strong low pressure system remained stationary over the Rockies. The Midwest was unfortunately located at the boundary of the two competing weather influences. The high pressure system brought an abundant supply of warm and very humid air into the region while the low pressure center spun off regular disturbances across the plains which generated widespread thunderstorms. All of the weather systems were locked into place to some extent during the summer of 1993 by a persistent ridge of high pressure located over Alaska.