September heatwave almost over for Montreal

Lightning illuminates the sky over L'Ile Perrot late last evening. The storms produced heavy rain and strong winds and provided some relief from a sultry day. (ValleyWeather Photo)

 That was one of the warmest Labour Day Weekends across southern Quebec and Ontario in quite some time. Montreal flirted with record highs both Sunday and Monday as the mercury hit 31C (88F) and 32C (90F) respectively, missing the record high by tenths of a degree. Other parts of the region were as warm as 34C (94F) and I recorded the second warmest day of the summer on L'Ile Perrot as the temperature hit 33C (91F) on Monday. The hot weather was accompanied by high humidity which helped to push the humidex value to 41C (106F) in Montreal Monday afternoon. These temperatures are well above the normal high for early September of 21C (70F). Even the overnight lows have remained warm in the low 20's in Montreal.

It was a spectacular Labour Day holiday to cruise the canal and boardwalk in Sainte-Anne-de-Bellevue. What a way to end the summer. (ValleyWeather Photo)

It was back to school and work Tuesday heralding the end of another summer. Despite that, it was another warm and very humid day reaching 28C (83F) so far this afternoon. It will remain warm and muggy overnight with lows remaining in the low 20's. Wednesday should be the last day of this heatwave as we are forecasting a cold front to arrive in southern Quebec late in the day. Hazy sunshine will give way to some welcome showers and thunderstorms with a high of 30C (86F).

Last night some air mass thunderstorms produced severe weather from eastern Ontario across metro Montreal. The storms prompted a tornado warning from Winchester, Ontario south into the Seaway Valley. In Montreal vivid lightning, strong gusty winds and torrential rain swept the region around 10pm. The storm deposited the first rainfall of September at my home on L'Ile Perrot where 18mm fell in under 30 minutes. Winds gusted up to 110km/h with the storms knocking out power to over 23,000 hydro Quebec customers. Those affected were mainly in the Lanuadiere region, but 5000 were affected in metro Montreal as well.