The seemingly simple question has two different correct answers, depending on whether you are following definitions (based on Earth’s tilt and orbit around the sun) or meteorological definitions (based on the annual temperature cycle and calendar for record-keeping).

While meteorological winter is fixed, the start of astronomical winter can shift slightly between December 20 and December 23. This variation happens because:

: This system was created for consistent data collection and weather forecasting. By dividing the year into four fixed three-month periods based on the calendar month rather than Earth's position, meteorologists can more easily compare seasonal statistics year-over-year.

Winter is more than just a drop in temperature; it is a celestial and atmospheric event with multiple "start" dates depending on whether you are looking at the stars or your local weather station.

For the majority of people, winter does not start on a specific date. It starts when the "vibe" is right.

The Execution: 6/10 User Experience: Variable

This system splits the year into four seasons of three full months each, based on the annual temperature cycle. It ignores the stars and focuses entirely on thermometers.

In the Northern Hemisphere, winter generally begins on either or December 21 , depending on whether you follow the meteorological or astronomical calendar. In the Southern Hemisphere, these dates shift to June. The Two Definitions of Winter

A solid seasonal transition, though the pacing drags in February.