A breath of spring in central Canada is yielding to a blast of winter on Wednesday.
A weather system tracking south of the Great Lakes is expected to dump 10 cm of snow or more on southern Ontario, Quebec and the northern Atlantic region while lashing Nova Scotia with a mix of snow and rain.
Temperatures in southern Ontario will plunge from a forecast high of 8 on Tuesday to -7 by Wednesday afternoon and sink to winter-like readings of -15 overnight.
In Ontario, winter storm warnings are in effect on shore of Lake Ontario from Kingston to Cornwall, where up to 15 cm of snow is predicted in some areas, and from Windsor to Niagara, where up to 25 cm is being called for by Wednesday night.
In Quebec, a similar winter storm warning is in effect from the Montreal area across to the Eastern Townships and Beauce.
Environment Canada says snowfall amounts up to 35 centimetres are expected in New Brunswick starting today and continuing Thursday.
Strong winds and blizzard conditions are expected in northern areas, while southern New Brunswick should prepare for ice pellets and freezing rain in addition to heavy snow.
Rain will be the biggest problem in Nova Scotia, where between 20 and 50 millimetres are expected with the possibility of blowing snow, ice pellets and freezing rain in northern areas.
Similar conditions are expected for parts of Newfoundland.
Along the island's south coast, forecasters say warm temperatures and heavy rainfall could lead to a significant snow melt and localized flooding.
Heavy snow, strong winds, freezing rain and ice pellets are also in the forecast for parts of Prince Edward Island.
Motorists are being advised to be careful on the roads.
With a file from Canadian Press