Starting Tuesday night, all southbound travel lanes of the Seaford-Oyster Bay Expressway between Hempstead Turnpike and Merrick Road in the towns of Hempstead and Oyster Bay will be closed on weekdays from 9 p.m. to 5 a.m., the state Department of Transportation said.

Southbound motorists on the expressway, also known as Route 135, can expect to be detoured at Route 24/Hempstead Turnpike to Route 107/Hicksville Road, officials said.

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The overnight closures, expected to last about three to six weeks, are needed for pavement and median work, as well as safety improvements, the DOT said.

"To maintain the safety of motorists, the speed limit is reduced throughout the construction area and work is taking place during off-peak daytime and nighttime hours," officials said in a release.