The George P. Coleman Memorial Bridge will be closed to traffic two nights next week, unless the contractor can release traffic one or more times each night through the work zone.

Nora Chivers, a spokesman for the Virginia Department of Transportation, said that the plan is to close the bridge’s southbound lanes from 10 p.m. Monday until 5 a.m. Tuesday for the installation of electronic message signs. Similar work to erect new message signs atop the northbound lanes is scheduled from 10 p.m. Tuesday until 5 a.m. Wednesday, Sept. 22.

However, the contractor won’t know until the work proceeds each night if any vehicles can pass through during a break, Chivers said, and some motorists may choose to drive back and forth to the Peninsula via West Point.

VDOT officials may have to reschedule the closures if inclement weather is forecast, such as wind and rain, and those traveling over the Coleman Bridge—which carries Route 17 over the York River between Gloucester P...