The weather front will hit the North West overnight Friday and into Saturday, bringing cold temperatures over night.
The Met office says Storm Oscar’s path has been unpredictable at times and says heavy rain will fall on Saturday along strong, gusting winds.
A Derry Strabane Markets spokesperson said: “Due to Storm Oscar a decision has been made to cancel tomorrows (Sat 3rd Nov) Wallled City Market, Guildhall Square.
“Haunted Harvest Market will finish today (Fri 2nd Nov) at 4 pm.
“The Walled City Market will resume next month on Sat 1st Dec.
“Apologies for any inconvenience caused.”