Flash floods in Texas, Oklahoma kill 2; 100s of homes gone

SAN MARCOS, Texas — Record rainfall was wreaking havoc across a swath of the US Midwest on Sunday, causing flash floods in normally dry riverbeds, spawning tornadoes and forcing at least 2,000 people to flee.

Tornadoes struck, severely damaging an apartment complex in Houston, Texas. A firefighter in Oklahoma was swept to his death while trying to rescue 10 people in high water. And the body of a man was recovered from a flooded area along the Blanco River, which rose 7.8 metres in just one hour and left piles of wreckage 6 metres high, authorities in Texas said.

"It looks pretty bad out there," said Hays County emergency management coordinator Kharley Smith, describing the destruction in Wimberley, a community that is part of a fast-growing corridor between Austin and San Antonio. "We do have whole streets with maybe one or two houses left on them and the rest are just slabs," she said.

From 350 to 400 homes were destroyed in Wimberley, many of them washed away, Smith said. Several people remained missing. Kenneth Bell, the emergency management coordinator in nearby San Marcos, said the damage in Hays County alone amounts to "millions of dollars”.

Authorities also warned people to honour a nighttime curfew and stay away from damaged areas, since more rain was on the way, threatening more floods with the ground saturated and waterways overflowing.

Rivers rose so fast that whole communities woke up Sunday surrounded by water. The Blanco crested above 12 metres — more than triple its flood stage of 3.9 metres — swamping Interstate 35 and forcing parts of the busy north-south highway to close. Rescuers used pontoon boats and a helicopter to pull people out.

Dallas also faced severe flooding from the Trinity River, which was expected to crest near 12 metres Monday and lap at the foundations of an industrial park. The Red and Wichita rivers also rose far above flood stage.

This May is already the wettest on record for several cities in the southern Plains states, with days still to go and more rain on the way. So far this year, Oklahoma City has recorded 69.52 centimetres of rain. Last year, the state's capital got only 10.9 centimetres.

The reasons include a prolonged warming of Pacific Ocean sea surface temperatures, which generally results in cooler air, coupled with an active southern jet stream and plentiful moisture from the Gulf of Mexico, said Meteorologist Forrest Mitchell at the National Weather Service office in Norman, Oklahoma.

"It looks like the rainfall that we're getting now may actually officially end the drought," that has gripped the southern Plains states for years, Mitchell said.

The storm system was pushing northeast Sunday after moving across parts of Colorado, central and North Texas and most of Oklahoma. New flash flood watches were issued Sunday for western Arkansas, Missouri and parts of Kansas.

About 1,000 people were evacuated from homes in Central Texas, where rescuers pulled dozens of people from high water overnight.

Five San Marcos police cars were washed away and a fire station was flooded, said Kristi Wyatt, a spokeswoman for San Marcos.

Wyatt said some 1,000 homes were damaged in San Marcos, Wimberley and elsewhere in Hays Count.

A tornado briefly touched down in Houston, damaging rooftops, toppling trees, blowing out windows and sending at least two people to a hospital. The weather service said the tornado struck with winds of about 160kph at around 6:30am Sunday. Fire officials said 10 apartments were heavily damaged and 40 others sustained lesser damage.

Some 80 kilometres north of the city, about 1,000 people were preparing to spend the night away from home. The Montgomery County Office of Emergency Management issued a mandatory evacuation order to more than 400 homes near an earthen dam at Lake Lewis that was at risk of failing due to the heavy rains.

Spokeswoman Miranda Hahs said the dam owned by Entergy Texas is holding, and that it was not clear when residents would be allowed to return home.

In northeast Oklahoma, Capt. Jason Farley was helping rescue people Saturday night when he was swept into a drainage ditch. His body was later recovered, Claremore Fire chief Sean Douglas said.

Colorado also was water-logged. A mandatory evacuation notice was issued Sunday for residents in the northeastern city of Sterling.