A £115,000 resurfacing scheme on the A50 Gilford Road, Portadown is due to start on Monday, July 31.
The 600-metre stretch extends from Princess Way to the national speed limit signs past the Breagh Road.
Work is expected to be completed by August 18.
Local access will be maintained throughout the duration of the works. Banbridge-bound traffic will be diverted via Gilford Road, Killicomaine Road, Old Lurgan Road and Drumnacanvey Road.
Portadown-bound traffic will be diverted via Mullahead Road, Brackagh Road, Tandragee Road, Mahon Road, Armagh Road, Church Street, Market Street, High Street, Castle Street, Bridge Street and Carrickblacker Road.
A statement issued by the Department of Infrastructure said, “The dates and duration of the works will be dependent on the progress of the scheme and on favourable weather conditions. In order to help ensure the safety of road users and road workers the public is asked to comply with all temporary traffic restrictions and to drive with care when travelling through, or in the vicinity of the works.
“Whilst the department has carefully planned these road works and associated traffic management arrangements in order to minimise any inconvenience to the public, motorists should expect delays and allow additional time when planning any journey.”
The department said the work “will deliver significant improvements to the structural integrity and the road surface quality of the Gilford Road”.