September Ends with Season’s First -20°C Temperature

September has marked a significant turning point in weather patterns as temperatures plunge toward winter. The country recently recorded its first sub-zero temperatures of the season, with a notable drop to -21°C in Eureka, Nunavut, on September 29. This is an early onset of winter, typically expected in early October.

Temperature Trends in September

Previously, on September 8, the mercury dipped below -10°C. Now, at the end of September, the region is experiencing temperatures that usually do not arrive until later in the year.

Factors Influencing Cold Weather

• The polar vortex has contributed to the significant cold, along with the movement of Arctic air.
• Temperatures have fallen sharply in both Nunavut and northern Quebec.

While regions in southern Quebec do not yet face extreme cold, they have experienced a cool spell. Temperatures in places like Gatineau reached 27.7°C the day before the cold front, demonstrating a stark contrast.

Upcoming Weather Forecast

This week, Montreal is expected to struggle to reach even 15°C, marking it as the coldest day. However, this brief cold snap is anticipated to be followed by a return to warmer conditions.

Potential for Spring-Like Weather

There is talk of possibly experiencing temperatures nearing 30°C in early October, an unusual occurrence. This follows a similar trend observed in October 2023, when Montreal came close to breaking the 30°C mark during an unusual heat wave from October 3 to 5.

As September concludes, these weather changes signal a shift towards a cooler season. The early arrival of -20°C temperatures serves as a reminder of the winter to come, even as warmer days may linger.