Spring snow, now heavy rain forecast for Montreal

A spring snow covers southern Quebec this morning, after 10 to 12cm overnight.

Heavy wet snow fell across eastern Ontario and southern Quebec late Wednesday and overnight, with a record-breaking 14.2cm in Ottawa. The previous record for April 6 was 13cm in 1958. Officially, Trudeau Airport reported 10.4cm, so our record of 18.3cm, also from 1958, was safe. I measured close to 12.5cm (5 inches) of snow here on L'Ile Perrot. Overnight, temperatures slowly nudged above the freezing mark, with precipitation changing to rain in Montreal. Temperatures will continue to rise today on warmer southeast winds, with a high forecast of 9C (48F).

Heavy Rain Warning
Low pressure will move from the central Great Lakes towards Lac Saint-Jean by Thursday night. A second wave of low pressure will move north towards Lake Champlain. The combination of these two systems will produce widespread heavy rain across the entire region. Expect 25-50mm (1 to 2 inches) of rain through early Friday morning. Environment Canada has issued heavy rain warnings for Montreal and a swath of southern Quebec. The rain and melting snow will cause sharp rises in some rivers and lakes, as well as produce minor street flooding. Behind the storm, colder air will move into Montreal overnight, with a low near 3C (38F). On Friday, showers mixed with snowflakes are forecast, with colder temperatures steady near 3C.