OTTAWA -- It may not be a white Christmas morning in Ottawa, but it will certainly be a wet one.

Environment Canada has issued a rainfall warning calling for significant rainfall Thursday into Friday morning. The weather agency says total rainfall amounts of 30 to 50 millimetres are likely, with localized flooding possible in some areas.

"Heavy rainfall totaling 30 to 50 mm is expected to develop Thursday and continue into Friday. The frozen ground will have a reduced ability to absorb this rainfall," Environment Canada says.

The warning is in effect for the City of Ottawa, Gatineau, and parts of region to the east and south of the capital and along the St. Lawrence.

Freezing rain warning for Upper Ottawa Valley

A freezing rain warning is in effect for the Upper Ottawa Valley, affecting areas from Arnprior up to Deep River.

"Several hours of freezing rain is expected tonight, particularly over higher terrain. Places along the Ottawa River, such as Pembroke and Petawawa, are not expected to be impacted by freezing rain as much as higher terrain areas to the southwest," Environment Canada said.

Up to 5 mm of ice accretion is possible in some parts of the region, which may lead to power outages.

FORECAST

Rain is expected to be heavy Thursday afternoon, but the bulk of the rainfall is expected to come in the evening. Thursday's high is 8°C.

Rain will continue through the evening and overnight as the temperature rises to 11°C.

On Christmas Day, the rain is forecast to end by the afternoon, and there will be a 30 per cent chance of flurries after the temperature drops to -2°C in the afternoon.

The forecast for Boxing Day includes a mix of sun and cloud, a 60 per cent chance of flurries, and a high of -6°C.