A rainy summary sequence
No, it’s not just an impression: the last summers were particularly “wet”. Indeed, Montreal has experienced a rainy series of rains over time with the 1920s, 2022, 2023 and 2024. These watered sequences seem increasingly common. “Before the 1990s, it happened that you had two consecutive wet. Since 1990, we have observed clusters of years with this same characteristic more frequently and longer durations, “notes Réjean Ouimet, meteorologist.
Rain more often and in greater quantity
Since 2010, there has been an increase of 17 % of the quantity of rain in Montreal in summer compared to the average of the period from 1991 to 2020. Besides, five of the richest Montreal summers of the last 83 years (2010, 2011, 2015, 2023 and 2024) have taken place since 2010.
-In the same line, the number of rainy days increased by 11 %. That’s not all: “The more significant events of 50 or even 100 mm have taken up more space in recent years, adds the expert Réjean Ouimet. Five episodes of more than 100 mm of rain took place during the summer of 2023 in Quebec, a novelty. »»
Why so much rain?
First, we will highlight the exceptional case of 2024. Montreal broke rain records that summer, especially due to the passage of the Tropical Storm Debby. Quebec had received more than 200 mm on August 9, 2024. Another culprit according to Réjean Ouimet: “Our last summers were hot, but also rich in humidity, which inflates the intensity of precipitation. »»
However, a hot summer is not systematically wet. For example, it will be noted that summer 2023 was watered with a normal temperature. What is more, among the 10 most watered summers since 1942, only three of them were hot.
Will summer 2025 be in the water?
If you are wondering if a wet spring is announcing a similar summer, the answer is no. According to the meteorologist Réjean Ouimet: “There does not seem to be an impact between spring and summer when it is abnormally watered. This happens in 30 % of cases. Besides, even if this spring 2025 was gray, it was not particularly rainy. As proof, the flood season was small. All that is said, that does not tell us if the summer will be yes or no to the water. It depends in part on a phenomenon that we keep under surveillance …
