First Day Winter 2025. Winter 2025 starts on sunday, december 21st in the northern hemisphere, with the first day of winter being the shortest daylight day of the year with the earth's axis having reached its furthest tilt away from the sun and begins to change directiion back. Next winter solstice saturday, 21 december 2024.
For the northern half of earth (the northern. Applications open for winter 2025 at 8:30 am: