Texas was walloped Tuesday by a band of thunderstorms packing high winds and torrential rains that damaged homes and flooded streets as they marched through the midsection of the Lone Star state.
In Denton, Texas, six children had to be rescued by boat from a school bus that stalled out in high water, Denton Assistant Fire Chief Kenneth Hedges said. The driver was eventually able to drive the bus to higher — and drier — ground.
On the south side of Denton, a student stranded by flash-flooding was able to drive off once the water receded, Hedges said.
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A severe thunderstorm watch remained in effect for a 350-mile long stretch of Texas as well as Oklahoma and parts of Kansas, Missouri, Arkansas and Louisiana. The big threats: Monstrous hail, "wind gusts of 70 mph, and "a tornado or two," the National Weather Service said.
Flash flood alerts were in effect in Texas' biggest cities — Dallas, Fort Worth, Houston, San Antonio and Austin — as well as in Little Rock, Arkansas, the Louisiana cities of New Orleans and Shreveport, and parts of Oklahoma, according to The Weather Channel.
In all, more than 15 million Americans were in danger of being drenched by a storm that was spawned in Mexico and crossed the border in Big Bend, Texas, increasing in strength and size as it headed northward.
People "in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings," the NWS warned. "Severe thunderstorms can and occasionally do produce tornadoes."
The storms were expected to weaken somewhat as they moved slightly eastward Wednesday, straddling the Texas-Louisiana border and covering Shreveport, Lake Charles and Baton Rouge.
NBC News meteorologist Bill Karins said storms like these — fueled by the jet stream dipping unusually low — are rare. "A strong jet stream rarely dips all the way into Mexico in March — or anytime — but that is exactly what is happening today," he said.
And because this band is not likely to be swept-up in the typical west-east "flow" of weather that moves across the U.S., the wicked weather will stick around.
"With nothing to push the storm along, it will linger ... for three days producing periods of strong to severe thunderstorms," Karins said.
So huge swath of the country — from the Gulf of Mexico north to Illinois, from central Texas all the way to Mississippi — could get anywhere from 3 inches to a foot of rain through Friday, with the heaviest precipitation in Arkansas, Louisiana and Texas.