LLANO COUNTY, Texas \u2014 A new round of heavy rain over an already-saturated watershed is expected to send a moderate to major flood surge down the Llano River Friday, according to CBS Austin meteorologist Avery Tomasco.<\/p>\n
At 2:30 a.m. Friday, Tomasco said a corridor of heavy rain was moving slowly through the Llano River watershed west of Mason County, adding to swells of floodwater the river was already carrying downstream. <\/p>\n
Because the ground was already saturated, Tomasco said, most of the additional rain was expected to run off directly into the river rather than soak into the soil. Now that the rain has ended, one more pulse of water will still need to work its way through the Highland Lakes system over the next day or two.<\/p>\n
Tomasco said that 2 to 4 inches of rain had caused the South Fork of the Llano River to rise 20 feet Friday morning, a surge that could send more than 60,000 cubic feet per second into Junction. The Johnson Fork, which enters the river from the southeast, was pushing an additional 25,000 cubic feet per second toward Junction, on top of roughly 16,000 cubic feet per second already flowing through the town, he said. <\/p>\n
The combined flow means the Llano River could see a “moderate to major flood” through Friday morning and afternoon in Mason and Llano counties.<\/p>\n
Tomasco said the rise would likely require more extensive floodgate operations at Wirtz and Starcke dams as soon as Friday night or Saturday morning to manage the incoming water.<\/p>\n