Days with many tornadoes in the United States have become more common over time. These days tend to occur in consecutive-day tornado events, but trends in the characteristics of consecutive-day tornado events have not been documented. The Mann-Kendall trend test and Theil-Sen slope estimator were used in this study to detect trends and estimate rates of change over time in multiple metrics of consecutive-day tornado events. Results show that the number of consecutive-day events, the number of days occurring in consecutiveday events, and the number of tornadoes occurring in consecutive-day events have decreased over time. The percentages of annual tornadoes and tornadodays occurring in consecutive-day events have also decreased over time. These trends suggest that the percentage of tornadoes occurring on isolated days has, alternatively, increased over time.
K E Y W O R D Sconsecutive-day events, tornadoes, trends