Already battered by flooding in Fredericton and the southwestern part of the province, New Brunswick is in for more severe weather, warns Environment Canada.
A major low-pressure system south of Nova Scotia will bring a mix of precipitation and strong winds over Dec. 20 and 21.
Rainfall of between 25 and 60 millimetres can be expected in the south, with strong northeasterly winds gusting up to 90 km-h for eastern coastal areas.
"These very strong northeast winds will create a significant storm surge along east facing coasts in the Gulf of Lawrence," the Environment Canada warning says.
"Very large pounding surf is also expected, which, combined with a run of high tides, will [cause] local flooding and coastal erosion during the high tide on Tuesday afternoon."
The head of the Bay of Chaleur, one of the hardest hit areas from the Dec. 6 flooding, will not be affected as badly, Environment Canada predicts.