At least three people have died and hundreds have been rescued following severe storms that moved across the southern part of Texas on Thursday and Friday.

Severe flooding in South Texas has left at least four people dead and forced emergency crews to rescue hundreds of people from rising waters. State officials say the Rio Grande Valley endured more than half of a year's worth of rain within the span of 48 hours last week, leading to submerged roads and waterlogged vehicles.

Severe storms dumped about half a year’s rainfall in two days, leading to flash floods across both sides of the border.

Significant severe weather and life-threatening flash flooding continue to impact much of the mid-South up through the Ohio River Valley.

Life-threatening flash flooding will continue and major river flooding will develop from the South into the Ohio Valley this weekend. Severe storms could also produce tornadoes, wind damage and large hail,

The 36-hour period from Friday evening into Sunday morning will be the most dangerous, as an additional 6 to 12 inches of rain will fall over already drenched areas.

Parts of the Midwest and South faced the possibility of torrential rains and life-threatening flash floods even as many communities were still reeling from tornadoes that killed several people.

Tornadoes are sweeping across areas of the South and Midwest of the United States, leaving a trail of destruction and tens of thousands of homes without power. Flash flooding is expected to follow the violent storms as the National Weather Service warns of a threat to life.