Arctic air to surge into Quebec to start April

Arctic air will surge south into Quebec and Ontario to start the month of April. AccuWeather.com

The final few patches of snow are melting away here on L'Ile Perrot, as the March sun begins to warm us up. High pressure will give southern Quebec a sunny and mild Wednesday, with light winds and temperatures warming to 12C (54F). Sadly, that is the end of the good weather news. Strengthening low pressure will approach southern Quebec from the central US on Thursday, with showers and thunderstorms. Rainfall amounts once again may exceed 25mm (1 inch) in many areas of Quebec and Ontario. Rainfall warnings have been posted by Environment Canada for regions north of Toronto, through the Ottawa Valley, and north of Montreal. It will be mild and breezy, with high temperatures near 15C (59F) in Montreal on Thursday.

On Friday, the first of two arctic fronts will slip south of the St. Lawrence Valley, with much colder air pouring into southern Ontario and Quebec. Winds will increase out of the northwest, up to 50km/h, along with showers both Friday and Saturday. Temperatures will begin to slowly cool Friday, with the high Saturday only 5C (41F). The really cold air arrives over the weekend, as another arctic front crosses the region. Temperatures will plummet to well below freezing Sunday, with a high of only -4C (25F) forecast. By Monday morning, low temperatures will be in the minus teens across southern Quebec. The cold will be accompanied by gusty northwest winds and some snow. It will feel like mid-winter into the early portion of next week. Snowfall, at this time, is expected to be light in Montreal, but more significant across the higher elevations of Quebec and New England, and especially close to the Great Lakes. A swath of lake-effect snow is possible this weekend and early next week.