Dangerous flash flood threatens Austin

AUSTIN (KXAN) - An incredible flash flood developed early Wednesday morning in Central Texas as Tropical Depression Hermine lifted slowly northward from the Hill Country into the Big Country.

Some 6- to 15 inches of rain were reported in many locations from San Antonio to Killeen, including most of Hays, Travis and Williamson counties.

Numerous water rescues were reported overnight. Many roads were closed, and some evacuations were ordered, particularly in Williamson County.

Brushy, Onion and Barton creeks and the Colorado River were all under Flood Warning early Wednesday.

Very heavy rain fell directly into Lake Austin, with more than 12 inches recorded at Mansfield Dam. Runoff from Bull Creek also flowed into the lake, forcing the LCRA to open flood gates on Tom Miller Dam.

As a result, the level of Lady Bird Lake was rising, causing minor flooding in low lying areas along Cesar Chavez and Austin High School.

Here's the latest information from the LCRA:

Outer bands from Tropical Storm Hermine are training over Travis County. Rainfall totals over Austin and surrounding areas continue to mount, but appear to be decreasing in intensity for the moment. Overnight heavy rains fell over Lake Austin downstream of Mansfield Dam and Lake Travis, the only flood control reservoir in the Highland Lakes system. Twelve to thirteen inches of rain were recorded at the upper end of Lake Austin at Mansfield Dam. Eleven to twelve inches of rain fell over portions of the Bull Creek watershed, tributary to Lake Austin. At Tom Miller Dam, which forms Lake Austin, floodgate operations to control the level of Lake Austin began at 10:30 p.m., and up to five floodgates were opened shortly before 1:00 a.m. to pass flood inflow to Lake Austin and control lake level.

Releases from Lake Austin will combine with additional inflows downstream of Austin. Below Austin, the Colorado River at Austin remains above flood stage. Barton Creek rose above flood stage from 1:30 a.m. to 2:30 a.m. this morning, and remains above bank full stage. High flows at Austin will reach Bastrop, Smithville and La Grange over the next one to two days. The latest river forecasts from the National Weather Service River Forecast may be accessed from the links below on this page.

Hermine continues to move northward across the watershed of the Highland Lakes. Rainfall over the upper basin above the Highland Lakes has slowed or stopped. The outer band of rain that has been training over Austin since late yesterday is continuing. Lake Travis is rising slowly. Runoff above the Highland Lakes has not been great enough to warrant flood operations at any of the Highland Lakes dams, except Tom Miller Dam. However, LCRA continues to monitor this storm closely. LCRA urges residents to monitor NOAA All Hazard radio broadcasts and local news media to stay aware of conditions affecting their local areas.

The threat for rain will begin to taper off Wednesday afternoon into Wednesday evening as the remnants of Hermine move north of our region. By sunrise Wednesday morning, the center of Hermine is forecast to be near Abilene, reaching Wichita Falls by midday Wednesday.