A powerful storm system bringing heavy rain to millions across parts of Texas and the southern Plains, including Oklahoma, Arkansas and Missouri, is expected to peak in intensity Thursday.

A Flash Flood Emergency was issued for areas in Concho, McCulloch and Menard Counties in Texas until 4:30 p.m. CT with a catastrophic threat stemming from extreme rainfall in the area. 

According to the National Weather Service San Angelo, in Menard County, 8.5 inches of rain have fallen, and flash flooding is already occurring, with additional rainfall amounts between 3 and 5 inches possible in the warned area, which will worsen existing flooding. 

The NWS urged residents in the affected areas to seek higher ground immediately due to life-threatening flash flooding. 

Flash flood warnings were issued over the Dallas-Fort Worth Metroplex Thursday morning, while Kerr County and other parts of Texas Hill Country dealt with 3 inches of rain that fell in the span of a few hours overnight. 

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Severe storms brought golf ball-sized hail to areas outside Tulsa, Oklahoma overnight Thursday.

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Flood Alerts remain in southeastern Texas and expanded to cover Dallas on Thursday morning.

High water slowed traffic on Interstate 30 in Rockwall, Texas during the morning rush.

Texas Gov. Greg Abbott activated state emergency resources on Wednesday morning before storms developed over the region.

NOAA‘s Weather Prediction Center has placed Southeastern Texas under a Level 3 out of 4 flash flood threat through Friday morning. This includes Del Rio and points east-northeast which could see over 5 inches of rain, all told.

Kerr County and other parts of Texas Hill Country warned residents to be aware of the flood potential on social media, some four months after the area’s deadly flood disaster on July 4th weekend.

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A Level 2 out of 4 flash flood threat has been issued for northern Arkansas, eastern Oklahoma and southern Missouri. This includes cities like Fort Smith, Arkansas, Tulsa, Oklahoma and Springfield, Missouri.

Some storms in this system have a chance of becoming severe later Thursday afternoon and evening, as the heavy rain shifts north and east away from Texas Hill Country.

According to NOAA’s Storm Prediction Center, isolated hail, strong wind gusts, and even a tornado or two are all possible across Central and North Texas, Oklahoma and Arkansas.

The Weather Prediction Center has issued a Level 1 out of 5 risk of severe thunderstorms for a broad area covering some 20 million, including the San Antonio, Dallas and Austin metro areas.

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Despite the flood threat, the rain is expected to be beneficial for cities like Oklahoma City, Tulsa and Shreveport, Louisiana, which have not recorded measurable rainfall since the end of October.