Flash Flood in Union County, Arkansas

West 19th Street and Tanglewood Drive was covered in high water.

A pre-frontal surface trough extended out in advance of a weak cool front over Western Arkansas and Southeast Oklahoma during the early morning hours of September 24th, with adequate forcing aloft associated with an upper level disturbance that ejected northeast ahead of an upper level trough entering the Southern Plains. A south-southwesterly low level flow yielded increased moisture and instability ahead of this surface and upper level disturbance, which focused an area of scattered strong to severe thunderstorm development during the early morning hours across portions of Southwest Arkansas. Damaging winds, large hail, and locally heavy rainfall accompanied these storms, with these storms later moving repeatedly over the same areas across portions of Southern Arkansas bordering Louisiana. Thus, areas of flash flooding was observed across portions of Columbia County before these storms weakened by mid-morning. As the cool front entered the region by early afternoon, strong heating contributed to increased instability, with large scale forcing along the front and ahead of the approaching upper trough yielding additional scattered strong thunderstorms containing heavy rainfall across portions of Southern Arkansas that had received substantial rains earlier that morning. Thus, flash flooding was observed across portions of Union County before the storms weakened and exited the region during the mid-afternoon hours.