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  • Illinois tornadoes


  • This report presents the climatology of Illinois tornadoes based on data from the 1916-1969 period, and offers a variety of general interest tornado facts. Illinois ranks eighth nationally in the number of tornadoes, but first in deaths and second in tornado damages. On the average, there are 10 tornadoes per year, occurring on five days. The annual average death rate from these storms is slightly over 19with an injured average of 110 people. A majority (65 percent) of Illinois tornadoes occur during March through June, with 15-21 April being the prime 7-day period. Over 40 percent occur between 1500 and 1800 CST, and 65 percent take place from 1400-2000 CST. Five of the outstanding Illinois tornado days of the 1916-1969 period are discussed in detail, including the famed Tri-State tornado of 18 March 1925, the most devastating tornado in the United States since systematic collection of tornado data began in 1916.The general information includes, among other items, basic definitions pertinent to tornadoes, safety precautions, formulation of a tornado forecast, and methods for remote detection of tornadoes.

Originally Deposited as: 999999993755

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Language(s): EN-English

Volume or Year: 1971
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Date Created: 9 24 2004
Date Last Modified: 5 13 2003

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1. Illinois tornadoes (20060927192113_ISWSC-103.pdf).
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