Rainy and chilly weekend forecast for southern Quebec

Quebec Public Security is currently monitoring the flow of several rivers in the Montreal region. Water levels are slowly on the rise in response to a wet start to April, combined with warm temperatures, melting snow and ice. More rain is forecast this weekend. The photo above was taken along the shores of Lake of Two Mountains during the major spring flood of 2019. (West Island Flood Volunteers Photo)

The sun finally broke out on Friday, albeit slightly cooler than Thursday, when south winds pushed temperatures into the upper teens. After a chilly morning low at the freezing point, along with wet snow, I managed a high of 21C (70F) on Ile Perrot Thursday afternoon. Under bright sunshine Friday, we should make it to 10C (50F).

Mixed precipitation late Wednesday, eventually gave way to scattered thunderstorms along with some heavy rain into the morning hours on Thursday. Trudeau Airport reported 24 hour rain totals of 25.4mm, I measured 32.4mm on Ile Perrot. 

All that rain, combined with any remaining snow and ice that is melting, has caused area rivers to be on the rise. Quebec Public Security is currently watching 8 rivers and lakes in the province, most of those in the southwestern corner, including Lake of Two Mountains at Sainte-Anne-de-Bellevue and the Rivière des Mille Îles at Terrebonne and Deux-Montagnes. Levels are also rising along the Ottawa River from Ottawa to Montreal.

All rivers will be watched closely this week as another wet and windy area of low pressure moves to the south of Montreal. This system will bring steady rain on Saturday, tapering to showers on Sunday. Between 15-25mm of additional rainfall is possible through Sunday.  The weather will be raw and windy this weekend, with temperatures just above the freezing point for many locations. There is a chance of some mixed wet snow or freezing rain at the onset on Saturday, especially for locations north of Montréal and in the Ottawa Valley.

Gusty winds of 30-60km/h are likely for the St. Lawrence Valley.

Another storm will take aim at southern Quebec on Tuesday, with a mix of rain and snow expected. Temperatures will be quite cold to start the work week.