Sioux Falls, SD – Heavy rain and thunderstorms will sweep across South Dakota tonight, raising the risk of flash flooding, especially east of Interstate 29. The National Weather Service warns that storms could deliver rainfall rates near 1 inch per hour, with widespread totals of 0.25 to 0.5 inches and isolated areas receiving 1 to 2 inches.
According to the Weather Prediction Center, flash flooding is most likely in southwestern Minnesota, where 4 to 6 inches of rain fell last night. A Flash Flood Watch remains in effect from 7 p.m. Sunday until 7 a.m. Monday for these saturated areas, including Redwood Falls, Marshall, and Canby.
Thunderstorms may also bring damaging winds and large hail, adding to travel hazards. Drivers are urged to avoid flooded roads and remain alert for rapidly changing conditions on urban streets and smaller creeks.
The highest flooding potential sits east of Sioux Falls, but localized flooding cannot be ruled out across much of eastern South Dakota. Residents in low-lying or flood-prone areas should be prepared to move to higher ground if necessary.
The Flash Flood Watch stays in place through early Monday, and additional advisories could be issued if storms redevelop.
