(Reuters) – Hot, humid weather on Tuesday is expected to bring thunderstorms and a risk of flash floods from Texas to the southeastern United States, after damaging overnight storms in the Northeast region of the country, the National Weather Service said.

The biggest flooding threat will be in southern and southeastern Texas, which could see several more inches of rain after getting drenched overnight, the NWS said.

Much of the northern part of the central and eastern United States had record-setting temperatures on Monday followed by strong overnight thunderstorms that downed some trees and caused flooding.

Rockford, Illinois, is expected to get more rain after flash floods on Monday night when storms dumped as much as five inches (13 centimeters) of rain in less than four hours. Emergency crews rescued people from numerous submerged vehicles.

Local power companies reported 18,000 outages in Michigan and 7,000 in New Hampshire, after overnight storms. Storms also caused scattered outages in Maryland, local media reported.

A slight-to-moderate risk of flooding remains in effect for Tuesday for areas along a front stretching from northern Illinois through the middle of Pennsylvania and New Jersey, the weather service said.

“Along that boundary we keep getting storms to fire up,” said Brian Hurley, a meteorologist with the NWS’s Weather Prediction Center in College Park, Maryland. “The heaviest rainfall is going to be along that front on either side of it.”

As the front drifts slowly south, it is bringing relief to areas north of it, including New England, New York, northern Pennsylvania, Indiana and Illinois, after those areas sweltered on Monday, Hurley said.

On Monday, record-high temperatures were tied or broken in 11 places in the Mid-Atlantic and Northeast regions, including Washington Dulles International Airport at 94 degrees Fahrenheit (34 degrees Celsius), Allentown, Pennsylvania, at 95 degrees and Albany, New York, at 97 degrees, the weather service said.

Temperatures south of the front are forecast to remain 5 to 10 degrees above normal during the middle of the week, with heat advisories in effect for the eastern Carolinas, southeastern Virginia and parts of Missouri and Illinois, the weather service said. An excessive heat warning was in place on Tuesday for the St. Louis area, it added.

(Reporting by Peter Szekely in New York; Editing by Scott Malone and Paul Simao)