YARMOUTH, N.S. -- People living in parts of New Brunswick and Nova Scotia are bracing for possible flooding as a slow-moving weather system threatens to dump between 50 and 100 millimetres of rain.

Forecasters say the low-pressure system will bring heavy rain and thundershowers to southern Nova Scotia and New Brunswick today and Friday.

Rainfall warnings are in effect in a number of counties in both provinces.

Environment Canada warns that heavy downpours can cause flash floods and localized flooding in low-lying areas.

Residents are being advised to watch out for washouts near rivers, creeks and culverts.