JEDDAH — The winter season, which lasts about 89 days, begins officially in Saudi Arabia on Saturday, according to the Jeddah Astronomical Society. The winter solstice, signaling the shortest day and longest night of the year in the Northern Hemisphere, occurred at 12:20 pm Makkah time on Saturday, Dec. 21. This day, when the sun shines directly over the Tropic of Capricorn, marks the beginning of winter astronomically in the Northern Hemisphere and summer solstice in the Southern Hemisphere. Eng. Majed Abu Zahra, head of the association, said that the winter solstice occurs due to the tilt of the Earth's axis by 23.5 degrees and its orbit around the sun. Therefore the northern and southern hemispheres exchange places in receiving sunlight, and therefore the tilt of the Earth and not the distance separating it from the sun is the reason for the occurrence of the four seasons. As the Northern Hemisphere tilts away from the sun, daylight hours become shorter, while the Southern Hemisphere enjoys extended daylight. Abu Zahra pointed out that the North Pole is tilted away from the sun on the day of the winter solstice and the sun apparently reaches the southernmost point in the sky, so all locations north of the equator have a day length of less than 12 hours, while areas south of the equator have a day length of longer than 12 hours. Mercury drops in most regions Meanwhile, the National Center of Meteorology (NCM) expects a cold air mass over the northern border regions, including Tabuk, Al-Jouf, and Hail, starting on Sunday, until Tuesday, with minimum temperatures ranging between zero and 4 below zero. In the same context, the NCM expects temperatures to drop again Saturday over the regions of Tabuk, Al-Jouf, the Northern Borders, Hail, and Al-Qassim, accompanied by active surface winds that stir up dust and dirt in the regions of Riyadh and Eastern Province, extending to parts of the Najran region, in addition to parts of the Makkah and Madinah regions. It pointed out that the sky will be partly cloudy to cloudy with a chance of light rain and fog in parts of the Jazan, Asir, and Al-Baha regions.
