Nova Scotia and Prince Edward Island will see the worst of the rain through Monday.
Brace yourselves, Maritimers.
Some parts of the Maritime Provinces could see as much as 75 mm of rain by the end of the day on Monday.
"The same trough that brought rain to the Great Lakes region and Quebec
is now bringing rain to the Atlantic Provinces," Weather Network meteorologist Dayna Vettese said Sunday morning.
Most of the rain on tap will be due to that trough stalling over the Maritimes, but Vettese said rainfall amounts may be higher after Sunday, when the system will start to tap into moisture from Tropical Storm Leslie
, which is expected to reach Newfoundland early this week.
"Once Leslie makes its track toward the Atlantic Provinces, we'll see more rain pick up," she said.
By Sunday morning, all of mainland Nova Scotia was under a rainfall warning, with up to 75 mm expected by the end of the day Monday.
The Prince Edward Island counties of Queens in Kings may get as much as 55 mm over the same period.
In New Brunswick, the Fundy coast and southeastern part of the province could get as much as 50 mm by tonight.
But depending on what track Leslie takes, forecasters warn amounts may be higher when all is said and done.