American Meteorological Society, Bulletin of the American Meteorological Society, 11(95), p. 1704-1712
DOI: 10.1175/bams-d-13-00252.1
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Media reports that clashing air masses produce tornadoes in the Central US mischaracterize the abundant new observational and modeling research on how tornadoes form. The consistent message in the media is that tornadoes form along the boundaries between air masses, such as cold fronts or drylines, with tornado formation being directly linked to the intensity of the 'clashing' between adjacent air masses. The reality is that air masses clash all the time, but frontal zones only produce tornadoes on relatively few occasions. Many tornadoes also occur outside of regions where air masses are clashing. In the relatively flat central United States, continental polar, continental tropical, and maritime tropical air masses meet easily, which is a factor in creating the baroclinic environments that favor extra-tropical cyclones.