Official Start Of Winter 2024 Calendar. When do the four seasons start in 2024—for spring, summer, fall, and winter? Winter solstice, the start of winter according to the astronomical calendar, is when the top half of the earth is tilted away from sun, while the bottom half is tilted toward the sun.

For the northern hemisphere, the winter solstice occurs every year on. Ending on 28 (or 29 during a leap year) february.