Quebec is preparing to host its first heat wave of the summer this week, when the thermometer should exceed 30 degrees between Tuesday and Friday. Sunday, in Montreal and in several other regions, the hot weather was already a reality. However, this first heat wave should be less oppressive.
“What we are monitoring at the moment is really a sequence of hot weather from Tuesday to next Friday, so three or four days where the maximum temperatures will remain around 30 degrees. It would potentially be a first heat wave in the province, ”explains Environment Canada meteorologist Amélie Bertrand.
In the immediate term, the hot weather expected on Sunday in several regions should not last. The thermometer is expected to drop back to seasonal normals for the day on Monday, around 23 or 24 degrees in Montreal, due to a mass of cold air from northern Quebec.
But it will only be a short respite. As of Tuesday, warm weather will return, exceeding 30 degrees in several regions. The sectors most affected by this heat wave should be Abitibi-Témiscamingue, Laurentides, Lanaudière, Outaouais, Montreal, Mauricie, Capitale-Nationale, Estrie and Beauce.
Less “overwhelming” heat
This first heat wave will be special, however, because “it will not be accompanied by a lot of humidity,” says Ms.me Bertrand. “These are temperatures ranging from 30 to 32 degrees, but in humidity value, it will be 32-34, she explains. It’s still a dry heat wave if we can say so, in other words it won’t necessarily be overwhelming, even if the sun will be very present. »
She explains the situation by the fact that an anticyclone is “stationary over southern Ontario and New England next week”, raises the meteorologist. “There will also be very little wind. The air will be dry, but with the accumulation of several days under the same conditions, we will still reach fairly high temperatures, ”notes the specialist.
Environment Canada also advises the public to avoid exposing themselves too long to the sun this week, and to drink plenty of water when this is the case.
After a cloudier and grayer spring, the coming week will therefore be very different from recent times. One issue remains, however, points out Amélie Bertrand. “The problem we have is that there hasn’t been much rain recently and there is no precipitation in sight. It can become problematic if there is no humidity and it remains dry, when you know that the fire indices are high at the moment. »
Note: such a temperature is quite rare in May, but not without precedent. Last year, a very wet heat wave was recorded from May 12 to 14. A “derecho”, a rare weather phenomenon that had not occurred since 1999, then caused violent thunderstorms, strong winds and significant material damage at the end of May.
“It’s not unheard of, but it doesn’t happen every year either. It sometimes happens that some summers, we see two days in a row at 30 degrees, but without having the three consecutive days which give a heat wave, ”concludes Ms.me Bertrand.
The earliest heat waves in Montreal since 1941
- May 17 to 19, 1962
- June 3 to 5, 1967
- May 21–23, 1977
- May 27 to 30, 1978