The National Weather Service has 14 active flash flood warnings in effect Thursday, up from 11 a day earlier, as the flooding threat both intensifies in Missouri and spreads to two states that weren’t on the map Wednesday: Alaska and Iowa.
Missouri remains the epicenter. The National Weather Service office in St. Louis has flash flood warnings covering a broad swath of the state, including Franklin, Washington, Montgomery, Warren, Howard, Cass, Henry and Johnson counties, with dozens more counties — from Buchanan and Clinton in the northwest to Cooper and Pettis in the central part of the state — under related flood products. In Washington County, radar indicated thunderstorms producing 2 to 3 inches of rain Thursday morning, with flash flooding reported as ongoing or imminent along Mineral Fork and other small streams. Elsewhere in the warned area, rain gauges measured 1 to 3 inches, and emergency management crews reported flash flooding causing road closures even as the heaviest rain moved out. The Weather Service says flooding of small creeks, urban streets, highways and underpasses will continue for a time even as rainfall intensity decreases.
The geographic footprint has shifted from Wednesday, when warnings stretched from the Washington, D.C. region through the Mississippi and Missouri River basins to South Texas. The Mid-Atlantic has dropped off today’s list, while Alaska and Iowa are now included alongside continuing warnings in Missouri and Texas. That reshuffling underscores how quickly flash flood threats can move as new rounds of thunderstorms develop over already-saturated terrain.
The pattern driving the warnings is a familiar one this week: repeated rounds of heavy rain falling on ground that has little capacity left to absorb it, so even modest additional rainfall is producing rapid runoff into streams and low-lying roads. The Weather Service’s warning language reflects that lag — several bulletins note that flash flooding is ongoing or expected to persist for hours after the heaviest rain has already passed.
The Weather Service’s safety guidance is unchanged and blunt: turn around, don’t drown. Most flood deaths occur in vehicles, and the agency notes that hilly terrain in the affected region is dotted with hundreds of low-water crossings that become dangerous during heavy rain. Residents in Missouri and Texas should expect additional warnings as the day develops, with the flooding threat likely to persist into the evening as saturated soils continue shedding runoff faster than it can drain.