After a bone-chilling start to the day, Montrealers can expect a gradual warming trend heading into the weekend, coinciding with a spectacular celestial event. The city awoke to a harsh reality on Friday, December 5, 2025, with temperatures plunging to a bitter minus-17 degrees Celsius at 5 a.m., feeling like minus-23 C with the wind chill.
The Weekend Warm-Up Begins
Fortunately, that marked the coldest point of the weekend. Conditions are forecast to improve throughout Friday, with the daytime high reaching minus-7 C under a mix of sun and cloud. The afternoon wind chill will make it feel closer to minus-13. Overnight, the low is expected to be around minus-9 C, feeling like minus-14 with the wind. This remains significantly colder than the average daytime high for December 5, which is typically around minus-1 C.
A Celestial Finale: The Cold Supermoon
Adding a silver lining to the cold snap is a breathtaking astronomical display. The twelfth and final full moon of 2025, known as the Cold Supermoon, rose on Thursday but will still appear full on Friday evening. According to experts at livescience.com, the moon will look especially magnificent when it rises about an hour after sunset. In Montreal, sunset on Friday is at 4:13 p.m., setting the stage for an early evening lunar showcase.
Looking Ahead to Saturday and Sunday
The weekend forecast offers a mix of typical December weather. Saturday is expected to bring flurries with a high of minus-1 C, providing a chance for some seasonal snowfall. Sunday will see a return to sunshine, though colder with a high of only minus-9 C. The brief reprieve from the extreme cold will be welcome for residents, perhaps making a moonlit stroll a more bearable prospect.
The scene of a solitary man and his dog on Mount Royal near Beaver Lake earlier in the week, captured in a photo on December 2, exemplified the quiet, frosty reality of Montreal's early December. As the deep freeze fades, the city can turn its eyes skyward for one of the year's most notable lunar events.
