AccuWeather.com

By Kristina Pydynowski, Senior Meteorologist

Sep 5, 2011; 5:35 PM ET

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Lee is no longer a tropical storm, but residents from the central Gulf Coast to the Northeast should not let their guard down.

Lee officially weakened below tropical storm status Sunday night after spending the day crawling through southern Louisiana.

However, the term "weakened" only applies to Lee's sustained winds. The severity of the flood danger Lee poses to places in its path has not diminished.

Earlier this morning, Lee's torrential rainfall prompted the issuance of a Flash Flood Emergency in central Mississippi.

The heaviest rain will fall west and south of areas hit by Irene

Tropical Rainstorm Lee still has potential to unload 4 to 8 inches of rain, with locally higher totals, from Mississippi to the southern and central Appalachians through Wednesday.

Widespread heavy rainfall is expected, forcing streams and rivers out of their banks. The smaller waterways will be the first to flood, and will do so rapidly. Next, rises will occur along the larger rivers as the runoff flows downstream.

Runoff flowing to these streams and rivers could trigger mudslides in the mountains.

According to Expert Senior Meteorologist Alex Sosnowski, "While the core of Lee's rain will fall west of some areas that were hit hard with flooding from Irene, part of the heavy rainfall will make the trip into the troubled areas of the Northeast."

Only if the bulk of the rain is spread out over several days would renewed flooding be avoided.

"Unfortunately, there is potential for a couple of inches of rain to fall in as many hours in part of the area, which would lead to flash and small stream flooding in portions of Pennsylvania, New York, New Jersey and New England," Sosnowski said.

"Interaction of Tropical Rainstorm Lee with a slow-moving front is raising the stakes for flooding in the Northeast. Downpours of that magnitude can occur any time through Wednesday," Sosnowski added.

Urban, low-lying and poor drainage areas are also highly susceptible to serious flooding issues.

Evident across New England as Irene moved through, the power of flood waters should not be taken lightly by residents and motorists.

Lee's Impacts into Tonight

Lee's heaviest rain will continue to inundate an area from Mississippi to the southern Appalachians, while spreading northward into the central Appalachians tonight.

Isolated tornadoes may touch down during this time east of Lee's center, from southern Mississippi to Georgia and the Florida Panhandle.

The steadiest of this rain will wait until tonight to reach the Interstate 95 corridor.

Flood Danger Lingers Tuesday into Thursday

Lee's heavy rain will leave the central Gulf Coast by Tuesday, then the southern Appalachians by Wednesday.

While it will not rain the entire time through midweek, the central Appalachians, mid-Atlantic and Northeast are in store for a dreary, cool stretch of weather Tuesday into Thursday thanks to Lee running into an atmospheric roadblock.

It is along the Appalachian Mountains where the rain may fall the heaviest and steadiest and lead to the most flooding issues.