A cold front slowly drifted across Kansas and Missouri on Tuesday, becoming situated near Interstate 70 by mid afternoon. A warm and very moist airmass was in place along and to the south of this front, providing plenty of fuel to fire strong to severe thunderstorms. A few of the stronger storms showed signs of strong rotation as they moved across parts of east central Kansas, prompting the issuance of tornado warnings. Storm spotters reported rotating wall clouds, funnel clouds, and a few brief tornadoes over Kansas and Missouri.
The moist airmass and relatively slow storm motion provided a favorable situation for thunderstorms to produce very heavy rainfall as well. Rainfall rates were estimated at 1 to 2 inches per hour with the heavier activity. Meanwhile, the very slow movement of the cold front allowed storms to repeatedly move over the same areas. This caused some extreme rainfall amounts estimated as high as 8 inches, and widespread flash flooding over much of east central Kansas. The following image is a radar estimation of storm total rainfall across the region. Yellow areas are rainfall estimates of 3" or more, while red indicates 5" or more, and the pink areas are in the 6" to 9" range.