On July 24, Environment Canada issued a tornado warning for the area around Lachute, Que., northwest of Montreal, urging people to take shelter. The warning was accurate: a tornado touched down outside Lachute about an hour after the alert. But three other twisters that day slipped past forecasters.
In the following days, the department confirmed that tornadoes had also formed on July 24 over the municipalities of Brossard and Boucherville, both located on Montreal’s South Shore, and west of Quebec City in Cap-Santé. None of those tornadoes was preceded by warnings from the department, which only issued extreme thunderstorm watches.
