Twice, the Texas Division of Emergency Management turned down Kerr County's requests for money to improve flood warnings.

Officials at the Comfort Volunteer Fire Department triggered a flood warning siren last week when the Guadalupe River began to swell.

More than 170 people are still believed to be missing a week after the forceful floodwater hit over the July Fourth weekend.

Following this weekend's devastating Texas floods that killed more than 100 people, and left at least two dozen still missing, outdoor warning sirens are now getting renewed attention.

When deadly floods swept through Texas, the National Weather Service issued a series of warnings that should have automatically triggered alerts to be sent to cellphones as the Guadalupe River began to rise.

Emergency officials are starting to focus on alert systems as they search for answers about how the flash flooding swept away so many.

State and local officials in Texas have come under scrutiny over the lack of sirens in place to warn people of impending flash flooding.

Center Point, Texas, RV park owner David Chambers said he was stunned not to have had a better warning as floodwaters rose.

Texas officials are being questioned about warning systems ahead of the deadly floods. As NBC News' Priscilla Thompson reports, Kerr County doesn't have a county-wide siren warning system in place.