NEW ORLEANS (CBSDFW.COM/AP) – Severe weather in Louisiana has left streets in New Orleans and parts of Orleans Parish underwater.

The National Weather Service has issued a tornado warning for Orleans and north-central Jefferson Parishes and there are concerns that even worse weather is on the way to Texas, Louisiana and other states along the Gulf Coast.

CBS 11 Meteorologist Anne Elise Parks said, “As of Wednesday morning, an area of low pressure continues to organize over the Northern Gulf. The current forecast shows this area of storms strengthening into a tropical depression later Wednesday or Thursday.”

The storms were associated with a broad area of disturbed weather in the Gulf that’s expected to become better organized by this weekend when it threatens the region with torrential rain.

Once it becomes better organized, the weather system could push the already swollen Mississippi River precariously close to the tops of levees that protect New Orleans, forecasters said.

The low pressure area is expected to strengthen into a storm as it moves west through the Gulf’s warm waters.

Lines of thunderstorms associated with the system on Wednesday extended far out in into the Gulf and battered New Orleans, where at least 3 inches of rain had fallen by mid-morning.

It’s expected to get much worse in the days ahead.

Parts of Louisiana could see up to 12 inches of rain by Monday, with heavier amounts possible in some spots, forecasters said.

“Louisiana and Mississippi appear to be the areas that would get the brunt of storm, but the forecast continues to evolve as the storm gets sampled while over open water,” Parks said. “While we do not expect direct impact, North Texas will need to watch for potential wrap-around showers and storm activity.”

The National Weather Service said New Orleans is protected to a river level of 20 feet, but it was forecast to rise above flood stage to 19 feet by Friday.

(© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)