Environment Canada has issued warnings for all of Nova Scotia. Heavy rain and freezing rain are expected from Monday night into Tuesday afternoon.
Rainfall across the province is expected to total between 25 and 50 mm.
Forecasters said conditions will worsen tonight, with rain intensifying in the southwest before spreading eastward overnight.
They added that the heaviest rainfalls are likely along the Atlantic coast by Tuesday morning.
Heavy downpours could lead to water pooling, flash floods, and localized flooding in low-lying areas.
Freezing rain is also forecast for northern parts of the province, including Cape Breton.
Ice buildup of up to 5 mm is possible, with freezing rain lasting four to six hours.
While it is expected to shift to rain by Tuesday morning on the mainland, freezing rain could linger in the Cape Breton Highlands into the evening.
Environment Canada is reminding everyone to prepare for changing weather and to use caution while travelling.