October 12, 2021

A Hurricane's Remnants Could Bring Flash Flooding To Texas This Week


Tropical Storm Pamela will make landfall on Mexico's West Coast as a hurricane late Tuesday night and quickly push inland over the next few days. Mexico's rugged terrain will tear the storm to shreds in a hurry, but the system's remnant moisture will continue into the south-central United States and bring a threat for flash flooding to Texas over the next couple of days.

The National Hurricane Center expects Pamela to regain hurricane strength before making landfall near Mazatlán overnight Tuesday into Wednesday morning. The system will quickly fall apart as it grates up against the steep mountains of central Mexico. However, a deep reserve of tropical moisture will continue flowing into Texas on Wednesday and Thursday.


Pamela's remnant moisture will reach central Texas at the same time as a cold front sweeping in from the west. Add in even more moisture flowing in from the Gulf of Mexico, and additional upper-level lift from the jet stream, and it sets the stage for very heavy rainfall across the region.

The latest forecast from the Weather Prediction Center calls for widespread rainfall totals of 2-4 inches for much of central Texas on Wednesday and Thursday, with the possibility for 5+ inches of rain in some areas. This may not sound like much, but the ground here is much more impermeable than in places like Alabama or Virginia. 


The WPC issued a moderate risk for excessive rainfall (in other words, flash flooding) across the areas expecting the highest rainfall totals. A moderate risk is usually a decent signal that widespread flash flooding is likely.

As such, flash flood watches are in effect for a wide swath of Texas and a portion of southeastern Oklahoma. The watches include San Antonio, Austin, Dallas, and Fort Worth. Flash floods are dangerous no matter what, but they're especially dangerous when they occur in heavily populated areas.

Driving through floodwaters is never worth it. It's impossible to tell how deep the water is until it's too late—or if the road is even still there under the water—and it only takes a small amount of moving water to lift up a vehicle and carry it downstream.


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I graduated from the University of South Alabama in 2014 with a degree in political science and a minor in meteorology. I ran Gawker's The Vane for two years and I've contributed to Mental Floss, Forbes, Popular Science, and the Washington Post's Capital Weather Gang. I also teamed up with Outdoor Life to write a book called The Extreme Weather Survival Manual, which came out in October 2015.

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