(Corrects governor's first name to Greg in paragraph 2)
By Steve Gorman
July 15 (Reuters) - A flash flood watch was posted across a broad swath of Texas on Wednesday as heavy downpours turned rivers into raging, life-threatening torrents and washed out more than 100 roads, leading to dozens of rescues of people stranded by high water.
The hardest hit region, according to Texas Governor Greg Abbott, was the Nueces River basin, which runs from a plateau northwest of San Antonio south through flood-prone Texas Hill Country areas devastated by flooding in July 2025.
Almost 140 people perished in last year's flood disaster, including 27 victims, mostly children, at Camp Mystic along the Guadalupe River, which flows roughly parallel to the Nueces. The two watersheds, both deluged in this week's rainfall, drain into the Gulf of Mexico.
Abbott, speaking to reporters at a late-afternoon news briefing on Wednesday, said no fatalities had been reported, and he urged residents of the area to heed flood warnings.
"There will be a lot of rising water for the next 24 to 48 hours," the governor said, adding that more than 75 people had been rescued, the majority of them stranded motorists. "We are dealing with and responding to a flood that is likely going to break records in Texas history."
Local news media footage showed roads and vehicles submerged in deep currents of muddy water that a state transportation official said had washed out at least 114 streets and highways at the peak of Wednesday's downpours.
'LIFE-THREATENING RAINFALL EVENT'
Abbott on Tuesday issued a disaster declaration for 59 counties in south-central Texas, encompassing roughly a fourth of the state, activating emergency response plans and 1,300 personnel from 30-plus agencies.
A flood watch was posted for most of the region, with a flash-flood emergency in effect for Kendall County, adjacent to San Antonio, Abbott said.
"This is a life-threatening rainfall event," state emergency management chief W. Nim Kidd told reporters, saying meteorologists had reported rainfall rates of up to 3 inches (7.6 cm) an hour.
Showers that began on Monday had dumped 10 to 15 inches of rain on the flood-stricken region by Wednesday, and another 10 to 15 inches was expected through Thursday morning, Abbott said.
Texas was not alone in facing a severe threat from torrential rain and high water.
The National Weather Service posted a flash flood watch for Thursday across much of central and southern Arizona, from Prescott and Phoenix south through Tucson and on to the Mexico border, due to heavy monsoonal storms sweeping the region.
Similar advisories were issued for the scenic canyon areas of southern Utah.
The heavy rains and flooding in the Southwest coincided with a prolonged heat wave bringing sweltering, humid weather to the Rockies, Northern Plains, Great Lakes and mid-Atlantic region, the weather service said.
(Reporting by Steve Gorman in Los Angeles; Editibg by Kate Mayberry)
