A record-breaking heatwave has moved across the Mid-Atlantic coast, causing “catastrophic flooding” in the upper Midwest, prompting evacuations and rescue efforts.

CNN
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Millions of people across the U.S. are still strugglingRecord heat wave The storm is moving toward the Mid-Atlantic coast, with many Americans facing “catastrophic” flash flooding this weekend, including parts of New Mexico, Iowa, Minnesota and South Dakota. Here’s the latest update:

• More than 8 million people are under a tornado watch. A tornado watch was issued for much of New England on Sunday, including all of Vermont and New Hampshire, as well as parts of New York, Maine and Massachusetts. The threat will remain in effect until 8 p.m. ET for cities including Burlington, Vermont; Albany, New York; Portland, Maine; and suburban Boston. A series of strong thunderstorms could produce tornadoes, wind gusts of up to 70 mph and hail the size of ping-pong balls, according to the Storm Prediction Center.

• Heat wave moves into Mid-Atlantic: With heat warnings remaining in effect for more than 100 million people through the weekend, the risk of extreme heat stretches from the Ohio Valley on Saturday to the Mid-Atlantic coast on Sunday. Highs in the Ohio Valley and Mid-Atlantic will be 10 to 15 degrees above average. “Extreme heat will continue in the Mid-Atlantic coast, with record high temperatures likely. In the West, triple-digit temperatures are possible in central and southern California, Arizona and Utah,” the National Weather Service said on its website Sunday.

• Temperatures break records: Baltimore and Washington DC were hit by triple-digit heat waves on Saturday. The US capital, Washington DC, topped 100 degrees Fahrenheit on Saturday for the first time since 2016. It was also the first time DC had recorded such temperatures this time of summer since 2012. Baltimore also recorded 101 degrees Fahrenheit, breaking the previous record for a 100-degree day set in 1988. The heat, which arrived early in the summer and continued for several days, “can raise the level of heat illness for those without reliable air conditioning,” the weather service said.

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• Flooding in Iowa prompts evacuations and disaster declarations: In Rock Valley, Iowa, flooding got so bad Saturday that every home north of Highway 18 was evacuated. “I can’t believe what I’m seeing,” said Daniel Haytritter, who evacuated his home in Spencer on Saturday. He said water in his home rose to his knees and he called for boats to stop and rescue him, his wife and their cat. On Saturday, Iowa Governor Kim Reynolds issued a disaster declaration for 21 counties in northwest Iowa and directed that all available state resources be deployed to help Rock Valley and other communities respond to the “catastrophic flooding.”

• People rescued from rising waters in South Dakota: In Sioux Falls, South Dakota, nine people were rescued from rising waters caused by heavy rains, city emergency manager Regan Smith said. Smith said emergency crews responded to five stranded drivers, 30 submerged vehicles, 10 water-related calls and 75 traffic accidents. Sioux Falls Mayor Paul TenHaken signed a state of emergency on Saturday in response to the flooding. TenHaken said the Sioux Falls area has received between 6.5 and 8 inches of rain in the past 72 hours.

• Minnesota prepares for emergency flood response: Parts of Minnesota were under flood warnings Saturday night, and Gov. Tim Walz declared a state of emergency and authorized the Minnesota National Guard “to provide emergency flood response operations support as significant flooding conditions continue across the state,” the governor’s office said. Water levels in Lake Tetonka and Lake Sakata reached “out of control.” “Residents are being evacuated and flooding has already caused significant damage,” the governor’s office said. “Intense rains are having devastating effects. Flooding has left entire communities under several feet of water, causing significant property damage and numerous road closures,” Walz said in a statement. Warnings remained in effect Sunday for the southern part of the state, northwest Iowa and southeastern South Dakota.

• New Mexico residents heading home after wildfires: The Salt and South Fork fires in New Mexico have burned more than 25,300 acres combined. As of Sunday morning, the South Fork fire was 31% contained and the Salt fire was 7% contained. Ruidoso residents will be allowed to return home on Monday, but officials have advised residents to bring at least a week’s worth of food and drinking water because grocery stores are not operating at full capacity. Rain in the area may help put out the fires, but it could also cause flooding and landslides in burned areas. Meanwhile, the FBI has offered a reward of up to $10,000 for information leading to the cause of the wildfires.

• Storm moves into New England: Severe thunderstorms ripped through parts of New England on Sunday, and heavy rain is expected to hit parts of the upper Midwest on Monday and Tuesday. Scattered high winds, tornadoes and hail are possible in New England. According to the Storm Prediction CenterElsewhere, monsoon-like weather could cause localized flooding in the Four Corners region, the weather service said.