When is winter? Weather forecasters in the Northern Hemisphere will tell you Dec. 1 through the end of February, which is known as meteorological winter. But based on Earth's tilt and orbit around the sun, it's Dec. 21, 2025, through March 20, 2026.
This is astronomical winter, which begins on the winter solstice with the shortest day of the year north of the equator and ends with the equinox (or "equal night") signifying the beginning of spring.
