Flash floods forced more than 1,000 evacuations and numerous rescues across Oklahoma and Texas, as officials warned a "historic" deluge was still to come on Sunday.
One firefighter in Oklahoma drowned after being swept away by flood waters. The heavy rainfall also washed out roads, trapped residents and knocked out power to thousands.
At least 60,000 customers were without power in Oklahoma and Texas on Saturday night — including more than 30,000 in the Austin area alone, The Weather Channel reported.
Flash flooding was expected to worsen across parts of Texas and Oklahoma as more torrential rains batter the already hard-hit region, according to The Weather Channel.
A state of emergency was in effect for 44 Oklahoma counties. The entire state was under flash-flood watches and warnings, and at least 15 highways were shut down due to flood waters.
One firefighter died after he was swept away by fast-moving flood waters in the city of Claremore, according to Oklahoma officials. Thomas Hudson, a Rodgers County emergency management official, said said the firefighter was trying to rescue civilians early Sunday when he was swept into the water and drowned. Several roads in and around the city were impassable and a few houses were flooded in Claremore, Hudson added.
Six inches of rain triggered flash flooding in Elk City, about 100 miles west of Oklahoma City. Elk City EMS said as many as 30 people were displaced.
The National Weather Service in Norman, Oklahoma warned motorists about the risk road conditions.
"This is a recipe for disaster," it said in a tweet. "DO NOT DRIVE INTO Water!"
Texas's Caldwell County — already experiencing flash floods — was bracing for a deluge from the San Marcos River on Sunday morning. Officials declared a "state of disaster," saying that rescues were taking place across the county and warning people not ot travel on flooded roadways.
A mandatory evacuation order was issued for all low-lying rural areas near the river and city of Martindale, according the county's emergency management coordinator.
Martin Ritchey told NBC News that 1,000 homes were affected by the evacuation order, with local sheriffs called in to assist in enforcing it and ensure locals were heading to higher ground.
"This is a historic flood," Ritchey told NBC News, adding that the San Marcos River was measured at a record 39-feet high. "The record before was 34 feet, now it is over 39 feet. That wall of water will be coming into our county."
Meanwhile, the Blanco River in Texas's Hays County rose more than 33 feet in just three hours — breaking an all-time record crest dating back to 1929 by nearly six feet, according to The Weather Channel. It said local authorities reported residents trapped on rooftops by the rising floodwaters.
The National Weather Service in San Antonio said early Sunday the river had risen 9 feet in just 15 minutes and was causing "catastrophic" flooding.
Hays County officials said "numerous rescues" were underway along the Blanco River in the Wimberley area, adding that additional officers have been called in to assist "with the situation."
Officials in Wichita Falls, in northern Texas, issued an evacuation order for residents living within a half mile on either side of the Wichita River, as they worried the river could crest more than once before Wednesday. City officials said the river was expected to rise one to three feet higher than when it did in 2007, when 170 homes were flooded.
Wichita Falls Mayor Glenn Barham said during a news conference Saturday that he would be "very concerned" if he lived in a flood prone area, with the National Weather Service warning of a "historic" flood event.
Tornado watches also were in effect for much of eastern Oklahoma and parts of central and south Texas overnight.
One large tornado was confirmed in Oklahoma's Grady County while several others were reported in the state on Saturday evening, according to The Weather Channel.
The wet and stormy weather was forecast to last into next week for the Plains, Texas and Mississippi Valley. While there will be a chance of isolated tornadoes, flooding will pose the main threat. Rainfall of between 1 to 3 inches could fall over the next week in Texas, Oklahoma, Kansas, Missouri and parts of Louisiana and Arkansas — and some areas could see 5 inches or more.
This story originally appeared on NBC News