The storm may have passed, but it will be a while before southeast South Dakota can dry out again.

The period between Tuesday night and Thursday morning dumped enough rain on the region to require road closures, water restrictions and evacuations, with conditions generally worsening throughout the day Thursday as water levels continued to rise.

By 1 a.m. Thursday, flood warnings were issued for all or parts of Davison, Aurora, Charles Mix, Gregory, Douglas, Hanson and Brule counties. As the day progressed, flood warnings were also issued in McCook, Hutchinson and Bon Homme counties.

"About 80 percent of our county is under water," Aurora County Emergency Manager James Nielson told The Daily Republic over the phone Thursday while standing in flood waters. "... We've received almost 8 inches in the last 48 hours, and it's just too much. There's no place for the water to go."

As is the case in most of the region, Aurora County has advised only necessary travel on most of its roads and has closed others. Nielson said the goal now is to preserve infrastructure and keep water moving downstream as much as possible.

Like Mitchell, Mount Vernon was placed on a water restriction after the storm, and the Sanborn County Sheriff's Office is encouraging limiting water usage in Artesian, Woonsocket and Letcher.

Interstate 90 was closed Thursday morning between Mitchell and Plankinton, and the state Department of Transportation closed the interstate between Mitchell and Sioux Falls on Thursday afternoon. The DOT advised that no one travel on the interstate between Kimball and Plankinton and said water has been reported over the roadway in many locations, and approaches have gone underwater. Signs and barricades have been placed, the state DOT said.

State Highways 37 and 38 were also placed under a travel advisory, and water has continued to wash out roads south of Mitchell. Following the storm, roommates Carter Neuschwander and Nathan Werdel walked through waist-deep water Thursday to evacuate their home at the intersection of 409th Avenue and 259th Street, where flooding spilled over from Enemy Creek, about a half mile west.

Farther southwest, travel on State Highway 46 is not advised from Pickstown to the highway's intersection with State Highway 50. A segment of Highway 46 from 5 miles east of Pickstown to a quarter-mile west of the Wagner junction has been closed, and travel is not advised on State Highway 42 east of Ethan.

Charles Mix County Emergency Management Supervisor Mike Kotab told The Daily Republic that as of about 9 a.m. Thursday, Platte Lake Road, which borders Lake Platte, had begun to wash out near the lake's spillway, which is something he hasn't seen before.

“It’s like a waterfall. It’s going down the spillway, but it took the road out next to the spillway,” said Kristi Pheifer, a Platte resident who observed the flooding Thursday morning. “...There’s a lot of people that live down the valley from there. It’s filling up the ditches along (State Highway) 44, too.”

Charles Mix County residents are being advised to be cautious on gravel and secondary roads.

"There's water all over. It's virtually across the county," Kotab said. "... It's a blur all together."

Hanson County Sheriff Brandon Wingert said his county has seen a similar problem and is also advising only necessary travel.

"We have flooded roads all over the county. Travel is extremely difficult.

"It's pretty much widespread. There's just a lot of standing water; a lot of water that's got to get downstream yet," Wingert said. "I'm being told by several county residents that travel is extremely difficult."

Lake Hanson, like Lake Platte, had its spillway go out on Thursday, though Wingert said the water is flowing into the James River and is not anticipated to impact any homes.

According to the National Weather Service, five South Dakota cities reached two-day rainfall records by Thursday. Alexandria and Howard received 8.3 and 7.05 inches of rain, respectively, beating previous records of 5.87 and 5.78 inches, which were set in both towns in 1893.

Bridgewater, which got 8.05 inches of rain, broke a previous two-day record of 6.25 inches, and White Lake and Madison broke records from 1909 and 1961.

While the rain had stopped by Thursday morning, many communities spent the day preparing for conditions to worsen as water levels continued to rise. Evacuation occurred Thursday in the lower-lying parts of Madison, which got more than 7.6 inches of rain over the two-day period. The Lake County Sheriff's Office asked people around Lake Herman to leave their homes, as the lake is expected to continue rising.

Shortly before noon on Thursday, McCook County Emergency Manager Brad Stiefvater Jr. decided to evacuate the town of Montrose, where many roads are already washed out, in anticipation of a large rise in the East Vermillion River. Evacuation was mandatory for First Avenue from State Highway 38 to Main Street.

Brad Stiefvater Sr., the county emergency manager's father who is also working at the county's emergency operations center, said the area has had power outages, adding difficulty for those with basements that don't have sump pumps.

"It's still rising, and we're looking for a big rise in Montrose," Stiefvater Sr. said Thursday afternoon. "We're being swamped with requests, and it's just starting to ramp up now, where people are being affected. Every bit of our resources are being used."

As of 4:50 p.m. on Thursday, NorthWestern Energy reported seven customers in Mitchell and four in Parkston who were without power. Natural gas systems were also flooded, primarily affecting customers in Mitchell, Corsica, Madison and Parker.