Sioux Falls, South Dakota – Waves of steady rain and embedded thunderstorms could drench parts of eastern South Dakota and northwest Iowa through late tonight, with isolated areas seeing over an inch of rainfall and potential flooding in low-lying spots.
According to the National Weather Service in Sioux Falls, two rounds of rainfall are expected Thursday, with the first arriving in the morning and a second, more widespread round pushing in from the south by early afternoon. Rainfall totals through midnight will range from 0.25 to 0.50 inches across central South Dakota—including Chamberlain, Mitchell, and Wagner—while areas east of I-29, like Brookings, Sioux Falls, and Le Mars, could see up to 0.75 inches or more.
Localized downpours in northwest Iowa may push totals past one inch, especially near Storm Lake and Spencer, raising concerns for ponding water and flash flooding in poorly drained areas.
Drivers should watch for slick roads and reduced visibility, particularly during the evening commute. Residents in flood-prone zones are advised to clear storm drains and avoid driving through standing water.
Rain is expected to taper off from west to east after midnight. Additional updates may follow if rainfall rates increase.
