When does winter start in 2025?

Arab Weather - Countries in the Northern Hemisphere are preparing to welcome the winter season of 2025/2026, which is expected to officially begin on December 21, 2025, and continue until March 20, 2026.

Astronomical beginning of winter

Astronomically, winter begins on the winter solstice. The date of the winter solstice in the Northern Hemisphere will be Sunday, December 21, 2025, while summer begins in the Southern Hemisphere. On this day, the sun reaches its farthest point south of the equator, resulting in the shortest day and longest night of the year. After this date, daylight hours gradually increase.

The astronomical start of winter is considered the official beginning of the season. The astronomical start of the seasons is determined by the tilt of the Earth's axis as it revolves around the sun, which causes the two hemispheres of the Earth to receive different amounts of solar radiation. Either one hemisphere tilts toward the sun, and it is summer, or it tilts away from the sun, and it is winter.

The beginning of winter according to the meteorological calendar

In meteorology, winter officially begins on December 1 of each year and lasts until the end of February. Scientists divide the seasons into fixed three-month periods based on climate patterns and the annual temperature cycle. This division differs from the astronomical seasons, which are based on the winter solstice, where astronomical winter typically begins on December 21 and lasts until March 20.

The purpose of adopting a fixed start for seasons in meteorology is to organize climate data and facilitate its archiving.

How does the weather change with the onset of winter?

As the northern hemisphere enters winter, the coldest period of the year begins. Temperatures drop further, the weather gets colder, and rainfall increases as the region is affected by frontal depressions that sometimes bring rain and other times snow. Frost is more common during the winter on very cold nights when the sky is clear.