NWC REU 2004
May 24 - July 31



A Study of Severe Weather Prior to Significant Tornado Occurrences

Courtney Hanna, David Imy, and John Hart



The purpose of this study was to determine if there was a pattern between strong to violent tornadoes and the severe weather preceding them. The study was based on a 13 year period between 1990 and 2002. Using the severe weather reports which were classified by time and distance preceding the strong/violent tornado, probabilities of occurrence were plotted against all strong/violent tornado cases, as well as the first significant tornado cases of each day. There were a total of 1,803 strong/violent tornado events during the study period, which included 10 F5, 95 F4, 406 F3, and 1,292 F2 cases.

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