00:48 Sioux Falls Tornado Rips Apart Building in Newly Released Footage Newly released footage from inside a health center in Sioux Falls shows the damage done by an EF-2 tornado that struck the city one year ago.

At a Glance Severe storms will target parts of the South Thursday.

The main threats are damaging winds, a couple of tornadoes and large hail.

Heavy rain could produce local flash flooding in already-saturated parts of the South and Southeast. On the warm side of Winter Storm Eboni's wintry wrath , severe thunderstorms and heavy rain will target portions of the South Thursday.

A southward dip in the jet stream has pushed into the south-central states. Ahead of that feature, moisture from the Gulf of Mexico is surging northward into the lower Mississippi Valley. This setup has yielded the development of severe thunderstorms.

At least two cars became submerged under water near Jackson, Mississippi, Thursday afternoon as heavy rain produced flash flooding in the area.

There were several reports of minor damage from a possible tornado northeast of Clarendon, Texas, late Wednesday afternoon. The reports included windows blown out of a home, trees damaged and some minor roof damage, according to the National Weather Service.

(LATEST NEWS: Severe Storms Damage Plane in Austin, Texas, Injuring Several)

Strong winds also caused damage near Dallas and in Wichita Falls, Texas, where a wind gust of 64 mph was measured.

Thursday's Thunderstorm Forecast

The threat of severe storms will shift eastward into the lower Mississippi Valley and parts of the north-central Gulf Coast.

An ongoing squall line will move through western Louisiana and coastal southeastern Texas Thursday morning, then continue eastward into eastern Louisiana, Mississippi and western Alabama during the day

Damaging winds and an isolated tornado will be the main concerns.

Heavy rain may also yield some areas of localized flash flooding from the northern Gulf Coast into the southern Appalachians.

Rainfall Forecast

The heaviest rainfall capable of flash flooding is expected to occur in parts of the Deep South and Southeast – many areas which do not need additional rain after an extremely wet year.

The most likely area for flash flooding is from eastern Louisiana into central Alabama, where NOAA has issued a moderate risk for excessive rainfall on Thursday. On Friday, the greatest risk for flooding shifts into northwestern North Carolina, northeastern Tennessee and southern Virginia.

Flash flood watches have been issued by the National Weather Service from southeastern Louisiana northeastward into western Virginia and southeastern West Virginia due to this heavy rainfall threat, which could lead to flash flooding and river flooding.

Over a dozen U.S. cities in the East and Midwest have already recorded their wettest year on record, with just under a week remaining in 2018.

Wilmington, North Carolina, crushed its previous record-wet year during Hurricane Florence in mid-September. On Dec. 15, the city reached 100 inches of yearly precipitation for the first time in records dating to 1871.

(MORE: 2018 Is Wettest Year on Record in Over a Dozen Cities)

In addition, yearly precipitation surpluses of more than a foot above average cover rather staggering swaths of the South, East and Midwest.

This includes Wilmington, North Carolina; Beaumont/Port Arthur, Texas; and Athens, Georgia, among other cities.

These areas will likely be under the greatest risk of flash flooding through late-week.