Radar-estimated rainfall totals across the South from Monday morning to Thursday morning.
CNN  — 

A multi-day deluge of rainfall across the South created dangerous and life-threatening flooding in parts of Texas, Louisiana and Mississippi this week.

More than a month’s worth of rain fell in several Texas and Louisiana cities from Monday to early Thursday, including Baton Rouge, Louisiana’s capital.

A flash flood emergency was issued Wednesday evening just north of New Orleans, in Mandeville, Louisiana, with the National Weather Service urging people to seek higher ground.

Mandeville saw 7.15 inches of rainfall from Tuesday evening to Wednesday evening, preliminary rainfall reports show. Of that deluge, 4.71 inches fell between 2 p.m. and 5 p.m. Wednesday, making for a 1-in-10-year event, according to rainfall analysis from CNN Weather.

While heavy rain is relatively common for areas near the Gulf of Mexico, experts say climate change is increasing the severity and frequency of such heavy rainfall events.

More than 14 inches of rain fell since Monday in Texas, and a few Texas cities picked up nearly double what’s typical for January.

Between 6 and 8 inches of rain fell in the College Station, Texas, area – about 80 miles northwest of Houston – from Monday to Thursday. The city picks up around 3 inches of rain on average in January.

Disaster declarations were issued in Texas for San Jacinto and Montgomery counties, north of Houston, due to extensive flooding from more than 8 inches of rain.

“The sheer number of roadways with high water or closed is too numerous to update consistently,” Montgomery County officials said on social media Wednesday.

Emergency officials in Montgomery County said they rescued 17 people and 15 pets who were trapped by floodwaters from the San Jacinto River Wednesday.

While the most intense rainfall is winding down Thursday, additional rainfall on Thursday could lead to flooding issues across portions of the Gulf Coast and Southeast.

CNN Digital Tracker Excessive Rainfall Outlook thursday 012524 pm.png

An area from southern Louisiana – including New Orleans – into parts of eastern Tennessee and western North Carolina is under a Level 2 out of 4 risk of excessive rainfall Thursday.

In Louisiana, a flood watch is in effect for New Orleans through 6 p.m. local time Thursday. The same alert is in effect for Jackson, Mississippi, through 6 p.m. local time Thursday while Birmingham, Alabama, is under the watch through 12 a.m. local time Friday.

An additional round of steady rain is expected to redevelop across the South on Saturday. This could cause flooding issues more easily in areas recovering from this week’s flooding.

Rain will also expand tremendously in scope Thursday through Saturday, bringing dreary, wet weather beyond the Gulf Coast to much of the East.

Around 1 to 2 inches of rain is possible during this time from the central Appalachians through New England.

CNN’s Aya Elamroussi, Andy Rose and Elizabeth Wolfe contributed to this report.