Texas, Oklahoma, Louisiana face possible tornadoes, large hail

Before you go, we thought you'd like these...
Before you go close icon

'Pray and Hold On': Family Recounts Riding Out La. Tornado

More than 15 million Americans were facing the threat of a severe thunderstorm capable of producing tornadoes, large hail and high winds which took aim at several states Tuesday.

The storm originated in Mexico and began crossing the border in Big Bend, Texas, early Tuesday. The storm started increasing in strength and size as it moved stateside.

SEE ALSO: JetSetJustine's trip to Dubai will give you a serious case of wanderlust

By 3:30 a.m. ET, a severe thunderstorm watch was in effect for a 350-mile-long chunk of Texas -- threatening "very large hail," wind gusts of 70 mph, and "a tornado or two," the National Weather Service said.

As the storm was set to increase, most of Texas -- including Austin, Dallas, and Houston -- as well as most of Oklahoma and small parts of Kansas, Missouri, Arkansas and Louisiana, were expected to be under threat of severe thunderstorms through Tuesday, according to The Weather Channel.

The NWS said that people "in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes," it added.

This threat of severe thunderstorms was forecast to have shifted eastward Wednesday, straddling the Texas-Louisiana border and covering Shreveport, Lake Charles and Baton Rouge.

See more of recent storms:

21 PHOTOS
East coast weather and storms, tornado Virginia
See Gallery
Texas, Oklahoma, Louisiana face possible tornadoes, large hail
WAVERLY, VA - FEBRUARY 25 The remains of a home lie in the path of destruction from a tornado that barreled through the small community of Waverly,the day before on February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25: Paul Logan, 21, talks about the tornado that barreled through the small community of Waverly, VA the day before on February 25, 2016 in Waverly, Virginia. Logan said it sounded like a bomb exploded in the front of his home during the storm. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25 The remains of a home lie in the path of destruction from a tornado that barreled through the small community of Waverly,the day before on February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25: A tree lays on a house a day after a tornado barreled through the small community of Waverly, on February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25 Sussex, County deputy, Larry Anthony, right, and Investigator, Eddie Oburn look over the remains of a home where two men and a child were killed when a tornado barreled through the small community of Waverlym the day before on February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25: Sussex, County deputy, Larry Anthony, (C) and Investigator, Eddie Oburn, (L), look over the remains of a home where two men and a child were killed when a tornado barreled through the small community of Waverly on February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25: The remains of the house that held 3 victims, two men and a child, when a tornado tore through the structure are seen February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VIRGINIA Ã FEBRUARY 25, 2016: Sussex, County deputy, Larry Anthony, left, and Investigator, Eddie Oburn look over the remains of a home where two men and a child were killed when a tornado barreled through the small community of Waverly the day before February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VA - FEBRUARY 25: The remains of the house that held 3 victims, two men and a child, when a tornado tore through the structure are seen February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
WAVERLY, VIRGINIA Ã FEBRUARY 25, 2016: Sussex, County Investigator, Eddie Oburn walks past a truck that was crushed by a tree during a storm the day before February 25, 2016 in Waverly, Virginia. Virginia's Governor McAuliffe declared a state of emergency after a storm system spawned tornados that killed four people on February 24, and the Virginia National Guard expects to have more than 50 soldiers on duty to help emergency response. (Photo by Jay Paul/Getty Images)
Timothy Williams looks over a car in front of his destroyed mobile home as he walks through debris left by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. Williams was in the car that he is standing next to when a storm swept through the area. (AP Photo/Steve Helber)
Laundromat manager Brad Poindexter, of Danville, Va., jumps over bricks at his damaged business after a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Laundromat manager Brad Poindexter, of Danville, Va., walks over bricks at his damaged business after a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Spectators walk through debris left by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Spectators look over debris left in the downtown area left by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Rahim Logan, left, and Antoinette Bendrick clear debris from driveway in front of their damaged home after a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Stairs and a destroyed foundation is all that is left from a mobile home that was carried across a highway by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
An overturned car rest on a highway next to the foundation of a mobile home that was throw across the highway by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. (AP Photo/Steve Helber)
Timothy Williams talks on a phone in front of his destroyed mobile home as he walks though debris left by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. Williams said he was in the car that he is standing next to when a storm swept through the area. (AP Photo/Steve Helber)
Timothy Williams talks on a phone in front of his destroyed mobile home as he walks though debris left by a deadly storm that swept through Waverly, Va., Wednesday, Feb. 24, 2016. Williams said he was in the car that he is standing next to when a storm swept through the area. (AP Photo/Steve Helber)
of
SEE ALL
BACK TO SLIDE
SHOW CAPTION +
HIDE CAPTION

According to NBC News meteorologist Bill Karins, the storm is rare because is being fueled by the jet stream dipping unusually low. "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.

This pattern meant the storm would not be swept up in the typical west-east "flow" of weather that moves across the U.S. "With nothing to push the storm along, it will linger ... for three days producing periods of strong to severe thunderstorms," Karins added.

Meanwhile, showers and thunderstorms were expected to dump between 3 and 12 inches of rain through Friday across a huge area from the Gulf of Mexico to Illinois, and central Texas to Mississippi.

The heaviest rain was forecast in Arkansas, Louisiana and Texas, and a flash flood watch was in effect early Tuesday across those states plus Oklahoma.

More from NBCNews.com:

Read Full Story

From Our Partners