Severe storms, flash flooding threaten holiday travel across the U.S.

Severe thunderstorms, flash flooding and extreme heat converged across the Plains, Midwest and South, putting roads, airports and outdoor events under pressure during a peak holiday travel window. The National Weather Service warned that risks were rising across the center of the nation, with large hail, damaging winds, tornadoes and numerous flash floods possible in the central Plains. Along the central Gulf Coast, it said life-threatening, potentially catastrophic flash flooding was expected.

The timing sharpened the threat for travelers. An estimated 94.5 million Americans were planning to travel by road or air during the holiday period, leaving little margin for delays as storms and heavy rain lingered along Gulf Coast states. Isolated brief tornadoes and damaging gusts also remained possible overnight in the Southeast, extending the disruption well beyond the hardest-hit storm zones.

Farther west, record warmth and dry lightning raised fire-weather concerns, adding another layer of danger to a weekend already shaped by extreme conditions. The National Weather Service’s June-to-August outlook favored above-normal precipitation across parts of the central U.S., including the Midwest, while above-normal temperatures were expected in parts of Colorado and western Kansas. That combination pointed to a summer in which heat, storm water and wildfire risk could overlap across a broad swath of the country.

The warning carried especially sharp resonance in Texas and the broader South, where flooding has already turned deadly. In the Texas Hill Country, a river rose 26 feet in 45 minutes during the July 4 flood, and more than 100 people were killed, including many summer campers. The speed of that disaster underscored how quickly water can overtake roads, campsites and low-lying neighborhoods when heavy rain stalls over one place.

With severe weather stretching from the central Plains to the Gulf Coast, the weekend’s hazards were not confined to one region or one type of traveler. Holiday motorists faced the prospect of flooded roadways and sudden detours, air travelers faced possible delays and cancellations, and outdoor crowds faced a volatile mix of heat, wind and lightning. The national outlook suggested the same pressures could keep building as summer advances.