Houston and much of southeastern Texas was paralyzed Thursday, Sept. 19, by heavy flooding caused by Tropical Depression Imelda, a deadly and catastrophic storm.

Over two years after Hurricane Harvey devastated southeast Texas, some say Imelda is worse. The National Weather Service calls it “an incredibly dangerous, life-threatening situation” and issued a flash flood emergency warning for several counties.

The storm could dump up to 5 inches of rain per hour in Harris County, where Houston was located, throughout the day Thursday. The county fire marshal reported more than 1,000 people were rescued or evacuated from flooded homes and roads in Harris County alone.

Harris County Sheriff said a man between 40  and 50, who was one of at least three people extracted from a submerged van died, FOX 26 reported. The van was submerged after the driver approached a freeway and then drove into water that was 8 feet deep.

Some areas saw more than 40 inches of rain, up to a foot more could fall Thursday night. Part of I-10 has become impassable. Traffic was unable to access I-10 east and westbound from FM 365 in Jefferson County to SH 73 in Chambers County.

And it’s far from over. Meteorologist of the Harris County Flood Control District Jeff Linder said, “We’re still putting water on top of water.”

Gov. Greg Abbott declared a state of emergency in 13 counties in southeast Texas, which were officially disaster zones. More than 75,000 homes and businesses were without power. A possible tornado was reported in southwestern Louisiana.

Houston Mayor Sylvester Turner and law enforcement officials cautioned everyone in the region to remain where they are and stay off flooded roads.

The meteorologist Eric Holthaus tweeted it was “one of the worst freshwater floods in American history,” calling Imelda “a 1-in-1,000 year rainfall event, just two years after [Hurricane] Harvey (also a 1-in-1000 year event).”

Imelda is now among the top five wettest tropical storm systems ever to strike the contiguous 48 states.

Emergency 9-1-1 call centers were overwhelmed with pleas for help, and in the Beaumont area, first responders lost count after 700 calls for help.

Houston’s George Bush Intercontinental Airport reopens, but many roads around the airport are flooded, airport officials tweeted. Many flights were delayed and more than 600 cancellations as of 3:20 p.m. EDT, according to flight-tracking service FlightAware. The airport reported getting nearly 6.5 inches of rain in two hours on Thursday morning.

Bus and rail services were also shut down throughout the region.