Texas flash flooding a 'worst-case scenario,' says former NOAA official

A retired National Severe Storms Laboratory employee in a Monday interview described the flooding in central Texas as a “worst-case scenario.”

“This really was a worst-case scenario where you had 6 to 9 inches of rain fall in just a few hours, right on top of that south fork of the river,” Alan Gerard, a meteorologist with 35 years of experience, said on “CNN This Morning.”

“And the unfortunate reality is all the soil and hills in that area just funnel all of that rainfall right into the river, and you can just get these tremendous flood waves that develop extremely quickly,” added Gerard, who worked for part of the National Oceanic and Atmospheric Administration (NOAA).

Gerard said scientists are not equipped to predict the severity of the flooding more than “an hour or two” ahead of time, which does not always provide people enough time to evacuate. There also is a risk that folks won’t receive that warning in time, since it’s so last minute.

“The unfortunate reality is we can do a pretty good job of identifying the kind of overall environment that’s supportive for flash flooding. But identifying the setup for a worst-case scenario like this — which this really was — is really beyond the state of what we can do right now,” he said.

Gerard said the National Weather Service issues flash flood alerts, which warn people that “conditions are ripe for this kind of a torrential rainstorm to occur,” but he acknowledged it’s unlikely that people will evacuate each time they get a flash flood warning — especially in these places prone to flash flooding.

“The reality is, if people evacuated or didn’t go into these areas every time there was a flood watch out, it would be very difficult for these places to operate because, I mean, it does happen fairly regularly, especially at this time of year. It’s a very flood-prone area. So, there’s always this balance,” he said.

Gerard said, ideally, scientists would be able to warn people of the severity of the storm six to nine hours ahead of time.

“That would have been a different situation and I think could have supported much more proactive actions, including potential evacuations,” he said.

"Unfortunately, we don’t have that kind of skill yet,” he added. “We’re working with research to try to develop modeling and approaches to forecasting that would enable us to better provide that kind of information, but, unfortunately, we’re just not really there yet.”

The death toll from the catastrophic flooding in Texas is nearing 90, and experts warn that number could continue to rise as search-and-rescue operations continue.