The National Weather Service issued timely alerts, meteorologists say, but few were listening in the hours before the early morning flash floods along the Guadalupe River

The first weather emergency alert sent by the National Weather Service with urgent language instructing people to "seek higher ground now" was sent at 4:03 a.m. local time.

Catastrophic flooding struck central Texas on Friday as the Guadalupe River surged by more than 20 to 26 feet within 90 minutes, causing widespread devastation and forcing mass evacuations in Texas Hill Country. At least 80 people have been killed in the floods while others remain missing or displaced and more than 850 people required rescuing.

Flash floods in Texas killed at least 82 people over the Fourth of July holiday weekend and left others still missing, including girls attending a summer camp. The devastation along the Guadalupe River,

Some 27 people, including nine children, have been confirmed dead after flash floods in central Texas, authorities said on Saturday, as rescuers continued a frantic search for survivors including dozens still missing from a girls' summer camp.