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.

The risk of the catastrophic flooding that struck Texas Hill Country as people slept on July 4 and left at least 120 dead was potentially underestimated by federal authorities, according to an ABC News analysis of Federal Emergency Management Agency data, satellite imagery and risk modeling.

Weather models that meteorologists use to predict thunderstorm activity and heavy precipitation suggested on Thursday the possibility of 10 inches of rain — and even as much as 20 inches — across

Q: Is it true that if President Donald Trump hadn’t defunded the National Weather Service, the death toll in the Texas flooding would have been far lower or nonexistent? A: The Trump administration did not defund the NWS but did reduce the staff by 600 people.

Maps show how heavy rainfall and rocky terrain helped create the devastating Texas floods that have killed more than 120 people.

Central Texas is infamous for its flash flooding and arid soil, hard-packed ground into which water does not easily infiltrate. So when rain hits the ground, it runs off the region's hilly terrain and canyons and accumulates into creeks and rivers rapidly, overwhelming them, causing them to rise quickly.

There are two types of natural disasters in this country. Sometimes, it’s the weather that’s getting worse, as climate change leaves Americans exposed to new risks in places they thought were safe. Sometimes, it’s the land use that’s getting worse, as high costs and lack of regulation push people into locations with long-standing known dangers.

Kerr County failed to secure a warning system, even as local officials remained aware of the risks and as billions of dollars were available for similar projects.

Weather model data shows the National Weather Service had reason to warn of higher flood risks. Still, meteorologists say the agency made reasonable predictions.

Shock has turned into grief across Texas where at least 120 people have died from flash floods and more were missing as the search for victims moved methodically along endless miles of rivers and rubble Thursday.