Environment Canada has issued a rainfall warning for many areas of the province, including St. John's and vicinity.
The weather office says a complex area of low pressure will "continue to meander southeast of Newfoundland today maintaining a moist northeasterly flow over the island."
A heavier band of rain extending right across the centre of the island, from Corner Brook to St. John's, is expected to begin to break up later today.
Rainfall warnings are also issued for Clarenville and vicinity, the Bonavista Peninsula, Gander and vicinity, Deer Lake-Humber Valley, Corner Brook and vicinity, Avalon Peninsula North and Grand Falls-Windsor and vicinity.
In the St. John's region, rain is forecast today at times heavy, and fog. The total amount is expected to be 40 to 50 mms.
Tonight rain or drizzle is forecast to change to flurries before Tuesday morning, with a risk of freezing drizzle during the changeover.
The rainfall amount tonight is expected to be about five mms.
Winds will be from the northeast 30 kms/h gusting to 50 kms/h today with a high of 1 Celsius.
Tonight winds will be about the same inland, but increase to about 70 kms/h along parts of the coast. The temperature tonight is expected to be steady near zero.
Tuesday's forecast calls for flurries, ending in the morning, then mainly cloudy, with a risk of freezing drizzle in the morning. Winds will be northeast 30 kms/h gusting to 50 kms/h, except 70 kms/h along parts of the coast. The high Tuesday will be around 2 Celsius.
Wednesday is expected to be cloudy with 40 per cent chance of flurries, low -2 Celsius and high 2 Celsius, while Thursday to Sunday, a mix of sun and cloud is forecast.
Environment Canada says rainfall today, combined with melting snow, could result in localized flooding.
The Royal Newfoundland Constabulary has advised motorists to slow down, considering water buildup on the streets and roads in the St. John's-metro region to avoid hydroplaning.