The Truth About Late Night Flash Flood Warnings and Risk

The Opinion of a Veteran National Weather Service Forecaster

I have closely monitored the happenings following the early morning Guadalupe River flash flood disaster (in the Texas Hill Country) on July 4, 2025 (one hundred thirty-six fatalities). I’m especially interested because I lived it before. I was on shift during the Albert Pike flash flood (in western Arkansas) during the predawn hours of June 11, 2010. Sadly, there was no way to monitor a rapidly rising Little Missouri River until it was too late. To date, this was the deadliest flash flood event on record in the state (twenty lives lost), and eerily similar to what happened in Texas.

In the image: Forecasters had no way of knowing (without reports) about a wall of water along the South Fork Guadalupe River southwest of Hunt, TX early on July 4, 2025, even though a Flash Flood Warning was in effect (issued at 114 am CDT). There were no gauges in the area. At Camp Mystic, twenty-seven people (mostly children) were killed. After detection by gauges downstream, the wall had a history of thirty foot rises within two hours after arrival.

The biggest concern I have with this type of event is risk. In the middle of the night when communication goes from a well-oiled machine to a tin can and string, it is increasingly more difficult to call attention to the threat as the flow of information wanes. If there is a lack of data, such as a shortage of gauges along a flashy tributary, it becomes a guessing game.

In the image: Forecasters were in chase mode between 300 am and 500 am CDT on July 4, 2025 while trying to determine the crest (in multiple Flood Warnings/Statements) along the Guadalupe River at Hunt, TX. The river finally peaked just after 500 am CDT (at 37.52 feet), and was over twenty feet above the initial guess.

Without much to convey, Flash Flood Warnings are great from a situational awareness big picture standpoint (high water is likely due to a lot of rain), but fall short on the fine details. Will the creek behind my house overflow? Maybe. A wall of water will not be found in the warning text until a forecaster is aware of its existence. And if the wall goes undetected, folks downstream are in trouble. The vulnerability to danger is high because nobody knows what’s going on.

In the image: Generally speaking, the location of the hazard is not defined as clearly in Flash Flood Warnings as Severe Thunderstorm and Tornado Warnings given a plethora of creeks and streams to consider.

While tags in Flash Flood Warnings are somewhat helpful in mitigating risk by describing the expected impact of a high water episode, they are not as effective without pinpointing when and where the threat will reveal itself.

In the image: This Flash Flood Warning (abbreviated with a “considerable” tag) mentioned heavy rain and the possibility of life threatening flash flooding at 335 am CDT on July 4, 2025. Meanwhile, a wall of water along the Guadalupe River (not in the warning) had already swept through locations to the southwest of Hunt, TX. A river gauge near town detected the wave, and forecasters were in the process of addressing the issue.

The “considerable” and “catastrophic” tags are designed to differentiate the garden variety flood from the flood of unusual severity or unprecedented flood. However, without a location of the monster and arrival time, those affected are inclined to assume a wait and see posture or one of indifference, which is not the desired outcome.

In the image: This is the first Flash Flood Warning (abbreviated with a “catastrophic” tag) mentioning a wall of water moving down the Guadalupe River at 534 am CDT on July 4, 2025. By this time, the river had crested at Hunt, TX, and forecasters were well aware of how deadly the situation had become.

The National Weather Service takes the job of protecting life and property very seriously. There is so much passion and dedication to take care of citizens in harm’s way. But, we don’t know everything, and sometimes the right thing to do is be honest. Even with a warning out, we may not have all the facts. That’s a message we should consider sending so it is understood a monster may be out there despite no reference to it. The risk is too high not to be transparent.

In the image: CREST (Coupled Routing and Excess Storage) Unit Flow values were at the top of the scale west of Kerrville, TX at 0920 UTC (420 am CDT) on July 4, 2025. This forecast tool indicated the likelihood of severe to unprecedented flooding due to extreme runoff from torrential rain. Even so, how the Guadalupe River would respond and to what degree was not known until rising water was detected by a gauge.

If this is a revelation to the outside world, then take this opportunity to improve the circumstances. The goal is to shift the focus from endangered to secured. Try to move the needle from complacency to a more proactive behavior. If the warnings are not enough, perhaps the knowledge of being susceptible to something terrible might boost the desire to stay safe. There are too many monsters hiding under the cover of darkness, and not enough willingness or technology to bring them to light. We need to work together to change the narrative, or this horror show will not stop playing.

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