First Day Of Winter 2025 Canada Map. The winter solstice, which marks the first day of winter 2025, occurs on saturday, december 21, 2025 at 4:21 a.m. — in 2025, the first day of winter is saturday, december 21.
The 2025 almanac predicts a winter with a “heart of cold,” forecasting big freezes and heavy. So, what is the winter solstice and why does it happen?