ABC News(NEW YORK) — Dangerous flash flooding is wreaking havoc in Texas with the remnants of Tropical Storm Imelda dumping massive amounts of rain overnight and into the morning.

The torrential rain prompted a full ground stop at Houston’s George Bush Intercontinental Airport on Thursday morning. The airport later reopened but officials warned of flooded roadways and delayed flights.

More than 33 inches of rain has fallen in the town of Hamshire, Texas, since Tuesday — and over 25 inches of that rainfall was overnight.

In the small town of Winnie, Texas, the conditions are “horrible,” with rapidly rising floodwaters making roads impassable, Chambers County Sheriff Brian Hawthorne told ABC News as the rain pounded down Thursday.

“This is the worst flooding I’ve ever seen,” Hawthorne said.

Some of the same houses flooded during Hurricane Harvey two years ago are now taking on water again, said Hawthorne.

The water has “run out of places to go,” the sheriff said.

Some homes have four to five feet of water inside, Hawthorne said, and dump trucks and airboats were being used to get people to safety. The sheriff believed about 45 people still needed to be rescued as of Thursday morning.

The local hospital stayed open but about one dozen patients were evacuated, he added.

“Until it quits raining, it’s gonna be a nightmare,” the sheriff said.

In Beaumont — between Houston and Lake Charles, La. — over 250 high-water rescue requests were called into 911, the local police department said Thursday morning.

“Please shelter in place and seek high ground,” the Beaumont police tweeted. “DO NOT drive.”

Rainfall rates up to 5 inches per hour were reported overnight near Beaumont, Texas, dumping the worst flooding since Hurricane Harvey.

The threat isn’t over. What’s left of Tropical Storm Imelda is still sitting over eastern Texas and western Louisiana, bringing more rain Thursday morning.

The remains of Imelda will then slowly track north on Thursday spreading rain into northeastern Texas, northern Louisiana and southern Arkansas and Oklahoma.

As much as 10 inches of additional rain is expected in eastern Texas and more flash flooding is expected in the next 24 hours.

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