Camp Mystic's executive director began evacuating campers approximately 45 minutes after the National Weather Service issued a "life-threatening flash flooding" alert.

Ground search operations were disrupted Sunday in Kerr County, Texas, where many lives were lost in the catastrophic July 4 flooding.

The official tally of storm-related deaths across Texas rose to 131 on Monday as authorities warned of yet another round of heavy rains 10 days after a Hill Country flash flood that transformed the Guadalupe River into a killer torrent.

A large percentage of people still unaccounted for were probably visiting the area, Kerr County Judge Rob Kelly said.

Here's what to know about the deadly flooding, the colossal weather system that drove it and ongoing efforts to identify victims.

Eight-year-old girls at sleep-away camp, families crammed into recreational vehicles, local residents traveling to or from work. These are some of the victims.

State and local officials said they did their best to coordinate evacuations and rescues, but better cellphone service might help in future floods.

Flash floods in Texas have killed at least 107 people over the Fourth of July weekend, with more than 160 still missing.

For the third straight day, thunderstorms have posed what meteorologists call life-threatening conditions in the Hill Country, where flooding earlier this month killed at least 131 people.