Floodwaters forced people out of their homes in parts of Iowa, the result of weeks of rain, while much of the United States longed for relief Saturday from yet another round of extraordinary heat.
Sirens blared at 2 a.m. in Rock Valley, Iowa, population 4,200, where people in hundreds of homes were told to get out as the Rock River could no longer take rain that has slammed the region. The city lacked running water because wells were unusable.
Mayor Kevin Van Otterloo said a state helicopter was on its way to help but was called off when boats were able to reach stranded residents.
''We've had so much rain here,'' he said. ''We had 4 inches last night in an hour and a half time. Our ground just cannot take anymore.''
Gov. Kim Reynolds declared a disaster for 21 counties in northern Iowa, including Sioux County, which includes Rock Valley. In drone video posted by the local sheriff, no streets were visible, just roofs and treetops poking above the water.
In South Dakota, Gov. Kristi Noem declared an emergency after the southeastern part of the state received heavy rainfall. The town of Canton, 30 miles (48 kilometers) southeast of Sioux Falls, has received 18 inches (45.72 centimeters) of rain.
Several highways were closed, including a key stretch of Interstate 29 south of Sioux Falls that later reopened. Sioux Falls, the state's largest city, had more than 7 inches (17.7 centimeters) of rain in three days.
''Even though the rain is slowing down, we need to keep vigilant,'' said Noem. ''The worst of the flooding along our rivers will be Monday and Tuesday.''