For the purposes of weather forecasting and climate data analysis, meteorologists divide the year into four seasons based strictly on annual temperature cycles. Because the astronomical dates shift slightly each year, meteorologists use fixed dates to make data comparison easier.
Even within the same hemisphere, there are two common ways to define the start and end dates of the season. Meteorological Winter Astronomical Winter December 1 December 21 or 22 (Solstice) End Date (North) February 28 (or 29) March 20 or 21 (Equinox) Basis Annual temperature cycles Earth's position relative to the sun Purpose Climatological record-keeping Traditional and astronomical marking when is winter season
Due to the elliptical shape of Earth’s orbit and the specifics of the calendar (including leap years), the dates of the solstices and equinoxes shift slightly each year. For the purposes of weather forecasting and climate
Winter is traditionally defined as the coldest season of the year. However, the specific timing of winter is not universal; it varies based on the method of definition (astronomical vs. meteorological) and geographic location (Northern vs. Southern Hemisphere). This paper outlines the three primary methods used to determine the start and end of the winter season. meteorological) and geographic location (Northern vs