A rainfall warning is in effect for western and southern portions of New Brunswick.
A deepening low pressure system just west of Nova Scotia will move northward to lie over the state of Maine tonight.
Up to 90 mm of rain could fall over parts of the region by tomorrow night.
Greater Moncton has escaped a rainfall warning but upwards of 30 mm could still fall.
UPDATE: A new rainfall record of 41.4 mm was set at the Greater Moncton Airport on Tuesday.