Published on July 11, 2023 at 9:00 p.m.
Difficulty sleeping, sweating, feeling unwell… Have you felt these symptoms in the last few nights? This is likely due to a nighttime heat anomaly currently marking Quebec. Explanations.
Amazing Predictions
Overnight temperatures of at least around 20 degrees Celsius are forecast for the week of July 12-18, 2023 in Montreal. For comparison, seasonal normals for this week should instead be around 17.1 degrees Celsius.
It is therefore a planned low temperature difference of almost three degrees, which leads to uncomfortable nights.
A growing trend
These sweltering nights of hot and humid temperatures are nothing new. In fact, this phenomenon has been increasing in Quebec for several years.
In Montreal, the number of hot nights in July has visibly increased in recent decades. Between 1961 and 1990, there were an average of 84 nights when the mercury read a temperature above 20 degrees Celsius, compared to 127 nights between 1991 and 2020.
The same observation applies to the Gatineau region, where the statistics have risen sharply, even nearly doubling. For the months July 1961 to 1990, 66 nights above 20 degrees Celsius were recorded. For the second period examined, from 1991 to 2020, no less than 123 nights above 20 degrees Celsius were counted.
Why is it so hot at night?
The main reason for this nocturnal phenomenon is the fact that humidity is currently at a high level. This results in warmer nights and limited body cooling.