The heat comes to Quebec, but not where you think

A weather always amazing

One of the pleasures of bringing meteorological phenomena is that they never cease to surprise us. We are not only talking about extreme events, but sometimes simple incongruities like the one that Quebec will live this week. While during the weekend, Mercury went down to -22 ° to Inukjuak and -9 ° to Radisson, it is in the same region that we will find the hottest point in Quebec at the start of the week. There will of course be a soft air push on the west of the province. But along the James bay coast should be the hottest place in all of Quebec on Tuesday. The great official is the effect of Foehn.

A wind that makes effect

When a wind crosses a mountain barrier, it is forced to rise along the slope in the wind. As the atmospheric pressure decreases and the air is cool. If the air is quite wet, its temperature can reach the dew point, which leads to the condensation of water vapor and the formation of clouds, and sometimes precipitation. Once the air has crossed the top of the mountains, it descends on the other side. Going down, the atmospheric pressure increases and the air warms up. This air, having lost moisture on the wind slope, is now drier and warmer. It is through this phenomenon in particular that the Valley of Death in California is the warmest place on the planet. Pacific air must cross the high mountains of Sierra Nevada before descending dried up and warmed on the valley.

Foehn warms the north

This is what will happen earlier this week north of Abitibi, in Jamesie. The air from the southwest will encounter reliefs, including the crest of Ishpatina, the highest point of all of Ontario, and will go down dried up and warmed up to Jamesie. Result: Waskaganish should be the hottest place in Quebec. There are also a maximum of 21 ° Tuesday afternoon, while in Montreal, we should not exceed 17 °, and the maximum planned in Quebec will be 15 °. The phenomenon will obviously be much less intense in Quebec than it is usually in the Death Valley. But for Jamesia and northern Ontario, it is still an anomaly of 10 ° to 15 ° above seasonal normal.

The north in advance

Waskaganish should therefore reach the magic figure of 20 ° as maximum before other Quebec cities which have still not had this chance. Mercury came close to 20 ° in Val-d’Or on April 28, but the maximum was 19.3 °. Situation similar to Rimouski on April 29, when the maximum was 19.6 °. Gaspé and Sept-Îles have not yet approached this brand, with maximums of 16.2 ° and 12.9 ° on April 28 and 29.

With the collaboration of Patrick Duplessis, meteorologist.

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