Swelling lakes and rivers in Florida continue to leave communities underwater in the wake of Hurricane Ian, and the historic flooding of at least one river could remain until Thanksgiving, according to the National Weather Service (NWS).

Storm damage and flooding from the St. Johns River, the longest river in the state of Florida, and its tributaries have affected at least 1,200 residents in Seminole County, officials have said.

The river has crested in multiple areas from Orlando to Jacksonville and recession will occur slowly, the NWS told FOX35 Orlando.

"The water at all of the points is starting to gradually decline, so we do see that very optimistically that the water is starting to recede, however it is very slow," NWS meteorologist Jessie Smith told the station. 

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NWS Melbourne forecast a 50% chance of showers and storms for Wednesday that could aggravate standing water and flooding along the St. Johns River Basin.

Residents of Geneva were rescued from inundated homes earlier this month as the floodwaters continued to rise after the storm had passed.

Seminole County Sheriff's Lt. Bobby Smith said at the time that the three or four days of rain that fell during the storm will eventually find its way to the river, which eventually leads into Lake Harney and then to Mullet Lake and Lake Monroe.

Since the St. Johns River flows south to north, communities downstream are likely to see floodwaters recede sooner, the station reported.