When do the four seasons start and end—for spring, summer, fall, and winter in North America? Find equinox and solstice dates for 2022—plus, answers to common questions. Do you know which season is shortest? Show Many folks assume the four seasons happen because the Earth is closer to the Sun in the summer (so it’s hotter) and then the Earth is farthest from the Sun in the winter (so it’s colder). This is incorrect. The Earth’s tilted axis causes the seasons. In fact, winter is when Earth is closest to the Sun (and visa versa). More on that in a moment. Our year (12 months) is commonly divided into four seasons, with each lasting about three months (but not exactly).
When Do the Seasons Start?However, the dates when the seasons begin and end vary depending on whom you ask. Each season has both an astronomical start and a meteorological start. It sounds complicated, but trust us, it’s not!
The First Days of the Seasons
Note: The dates above correspond to the start of the listed seasons in the Northern Hemisphere. Times are based on Eastern time (ET). Subtract 3 hours for Pacific time, 2 hours for Mountain time, 1 hour for Central time, and so on.  The Definition of a “Season”Here is more explanation about how astronomers and meteorologists define seasons differently:
The Old Farmer’s Almanac is an astronomical “calendar of the heavens,” so our book has long followed the astronomical definition of the seasons based on the Sun and Earth! What Causes the Seasons? As mentioned at the start of this article, the Earth’s tilted axis causes the seasons. The axis is always tilted in the same direction. So, as the Earth orbits the Sun over the 12 months of the year, different parts of Earth get the Sun’s direct rays Look at the diagram below. When the North Pole tilts toward the Sun, it’s summer in the Northern Hemisphere. And when the South Pole tilts toward the Sun, it’s winter in the Northern Hemisphere. Image: The revolution of Earth around the Sun produces seasons. Credit: NASA Why Has Date Changed for Start of Seasons?You may have noticed that the first day of spring used to be a different date when you were younger than it is today. The dates actually shift over time. Why? There are several reasons but the one that’s easy to understand is: The Sun doesn’t follow a human calendar! While our Gregorian calendar was designed to match the time it takes for the Earth to complete one orbit around the Sun, it’s not exact. Specifically, it eliminates leap days in century years not evenly divisible by 400, such 1700, 1800, and 2100, and millennium years that are divisible by 4,000, such as 8000 and 12000. Therefore, the dates of the equinoxes and solstices can shift by a day or two over time, which causes the start dates of the seasons to shift over time, too. Why Are The Seasons Different Lengths?It can sometimes feel like winter is dragging on forever, but did you know that winter is actually the shortest season of the year? (In the Northern Hemisphere, that is.) Why? Thanks to the elliptical shape of Earth’s orbit around the Sun, Earth doesn’t stay the same distance from the Sun year-round. In January, we reach the point in our orbit nearest to the Sun (called perihelion), and in July, we reach the farthest point (aphelion). Read more about perihelion and aphelion. When Earth is closer to the Sun, the star’s gravitational pull is slightly stronger, causing our planet to travel just a bit faster in its orbit. For those of us in the Northern Hemisphere, this results in a shorter fall and winter, since we are moving faster through space during that time of the year. Conversely, when Earth is farthest from the Sun, it travels more slowly, resulting in a longer spring and summer. (The opposite is true in the Southern Hemisphere.) In other words, it takes Earth less time to go from the autumnal equinox to the vernal equinox than it does to go from the vernal equinox to the autumnal equinox. Due to all this, the seasons range in length from about 89 days to about 94 days. The Four SeasonsWhat defines each season? Below is a brief explanation of the four seasons in order of calendar year. For more information, link to the referenced equinoxes and solstices pages. SpringOn the vernal equinox, day and night are each approximately 12 hours long (with the actual time of equal day and night, in the Northern Hemisphere, occurring a few days before the vernal equinox). The Sun crosses the celestial equator going northward; it rises exactly due east and sets exactly due west. See our First Day of Spring page. SummerOn the summer solstice, we enjoy the most daylight of the calendar year. The Sun reaches its most northern point in the sky (in the Northern Hemisphere) at local noon. After this date, the days start getting “shorter,” i.e., the length of daylight starts to decrease. See our First Day of Summer page. Autumn (Fall)On the autumnal equinox, day and night are each about 12 hours long (with the actual time of equal day and night, in the Northern Hemisphere, occurring a few days after the autumnal equinox). The Sun crosses the celestial equator going southward; it rises exactly due east and sets exactly due west. See our First Day of Fall page. WinterThe winter solstice is the “shortest day” of the year, meaning the least amount of sunlight. The Sun reaches its most southern point in the sky (in the Northern Hemisphere) at local noon. After this date, the days start getting “longer,” i.e., the amount of daylight begins to increase. See our First Day of Winter page. What’s your favorite season—and why? Let us know in the comments below! Is today officially fall?The autumnal equinox—also called the September equinox or fall equinox—arrives on Thursday, September 22. This date marks the start of fall in the Northern Hemisphere and spring in the Southern Hemisphere.
What days are fall?In the Northern Hemisphere, the astronomical Start of Fall is on September 22, at 3:21 P.M. EDT. This day is also known as the Autumnal Equinox. Fall is the transitional season between Summer and Winter. In 2021, Fall will last from September 22 until December 21, which is when Winter starts.
Is it autumn or fall now?Both are used in American and British English, but fall occurs more often in American English. Autumn is considered the more formal name for the season. The trees are turning; the weather's getting cooler; Pumpkin Spice Lattes are back—it's fall!
What day is first day of fall?If you reside in the Northern Hemisphere, you know it as the fall equinox (or autumnal equinox). For people south of the equator, this equinox actually signals the coming of spring. Your location on the globe also determines whether you mark the day this year on Thursday, September 22, or Friday, September 23.
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Is today fall
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