When Do the Seasons Start in 2021?

Celebrate the First Days of Spring, Summer, Fall, and Winter

June 9, 2021
Spring, Summer, Fall, Winter 360

When do the four seasons start—and why do the dates change for the start of spring, summer, fall, and winter? Here are the equinox and solstice dates for 2021 and 2022—plus, answers to common questions about why seasons’ dates may change, why the seasons are different lengths, and what’s the difference between an astronomical season and a meteorological season.

When Do the Seasons Begin?

Each season has both an astronomical start and a meteorological start. It sounds complicated, but trust us, it’s not!

  • The astronomical start date is based on the position of the Sun in relation to the Earth.
  • The meteorological start date is based on our 12-month civiil calendar as well as the annual temperature cycle. 

The First Days of the Seasons

Seasons of 2021 Astronomical Start Meteorological Start
SPRING Saturday, March 20, 5:37 A.M. EDT Monday, March 1
SUMMER Sunday, June 20, 11:32 P.M. EDT Tuesday, June 1
FALL Wednesday, September 22, 3:21 P.M. EDT Wednesday, September 1
WINTER Tuesday, December 21, 10:59 A.M. EST Wednesday, December 1
Seasons of 2022 Astronomical Start Meteorological Start
SPRING Saturday, March 20, 11:33 A.M. EDT Monday, March 1
SUMMER Sunday, June 21, 5:14 A.M. EDT Tuesday, June 1
FALL Wednesday, September 22, 9:04 P.M. EDT Wednesday, September 1
WINTER Tuesday, December 21, 4:48 P.M. EST Wednesday, December 1

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 astronomists and meteorologists define seasons differently:

  • The astronomical start of a season is based on the position of the Earth in relation to the Sun. More specifically, the start of each season is marked by either a solstice (for winter and summer) or an equinox (for spring and autumn). A solstice is when the Sun reaches the most southerly or northerly point in the sky, while an equinox is when the Sun passes over Earth’s equator. Because of leap years, the dates of the equinoxes and solstices can shift by a day or two over time, causing the start dates of the seasons to shift, too.
  • In contrast, the meteorological start of a season is based on the annual temperature cycle and the 12-month calendar. According to this definition, each season begins on the first of a particular month and lasts for three months: Spring begins on March 1, summer on June 1, autumn on September 1, and winter on December 1. Climate scientists and meteorologists created this definition to make it easier to keep records of the weather, since the start of each meteorological season doesn’t change from year to year.

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!

Temperate regions of Earth experience four seasons because of shifting sunlight, which is determined by how the Earth orbits the Sun and the tilt of our planet’s axis. As the Earth progresses through its orbit during the year, the tilt causes different parts of the Earth to be exposed to more or less sunlight, depending on whether we are tilted towards or away from the Sun.

Equinox solstice cycle
Photo 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 astronomical 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 its actually the shortest season of the year? (In the Northern Hemisphere, that is.)

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 Seasons

What 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.


On 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

Crocus field spring


On 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

Sunflower bees

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.

Fall leaves


The 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.

Winter solstice

What’s your favorite season—and why? Let us know in the comments below!


Reader Comments

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Autumn, Summer, Spring, and last of all winter. I loathe the cold & snow, although it's beautiful when pristine. As an aside, your 2022 calendar season start dates are off by one day. Each needs to be moved one day later in the week.


My favorite season is fall, because of the cool weather, shorter days, and foliage. My least favorite is summer, because of the heat, too much sun, sweat, and insects. In order:

1. Fall
2. Winter
3. Spring
4. Summer

The only good thing about summer is that my birthday is during the summer.

Winter solstice

Why the weather is most colder not on winter solstice but many days afterward

My Favorite season

My favorite season is winter. I love everything about it. The cold weather, the snow, shorter days, and most importantly the clothes you get to wear lol. Oh, and don't forget the boots boots! Although, fall is by far the prettiest season and a very close second for me.


Spring because I like the rain and I live watching all of the plants and flowers bloom.. and fall because I love that perfect temperature for jeans and a T-shirt and all the plants that change into beautiful colors. And I’m obsessed with pumpkins..

All the Seasons

I was raised on a farm in Oregon’s Willamette Valley. Spring time was a preparation for the summers harvest. The fields were so green and beautiful. Summer saw the entire family work together, bringing in the harvest. You could see your labor revealing itself into crops to sustain your family.
In autumn, fields were plowed, leveled, and new crops planted. By October, rains came, and the labor slowed. The beautiful maple trees changed their color. Cutting dead oak trees would provide heat a year from now. Green wood less than a year old smells in the air.
Winter was time to rest for all of us not attending school. Snow occasionally fell during Christmas.
School functions, State Fairs, Church, and occasional travels to Southern California in the Winter was always welcome.
Living in Oregon, you experience all four seasons. It is wonderful.


this is my favorite time of year because October is my birthday and the long hots summers are finally over in South Carolina not that I don't like summer but you get tired of the heat just like you do the cold living in Minnesota. moreover autumn is time for the state fair and the elephant ears and food on a stick and after you eat all that food a trip to Edisto Beach is in order to walk all that food off when the tourists have left for the summer and pick sea shells by the sea shore.

Definitely Winter

I have epilepsy so I can't be in the heat because of my sezures. So my favorite season is winter. I love going outside. It's fun. My family thinks I'm crazy because I love the cold so much.

Favorite season is fall into winter

I live in Alabama. The summer is awful. I hate hot weather and the AC bills. Used to like it as a child, but school was out. We rarely get snow but when we do everyone enjoys it. My husband was from Pa. and hated cold weather but He hated shoveling it too. But I will take cooler weather all the time.


After giving this a few minutes of thought, I've come to the conclusion that I truly like all four seasons for what each has to offer. I feel this is due to the transitions from one season to another.

When winter releases its grip and gives into Spring, it's a time of renewal. Ice and snow give way to green landscapes and flower buds. Late spring sees the trees becoming fuller and the whitetail fawns, full of spots, running in the fields.

By the beginning of Summer, vacations to the beech, and long days allow for getting a lot of fun crammed into the day. The last days of summer feel brutally hot and any relief would be welcomed.

Enter Autumn... The days get noticeably shorter and there is a crispness to the air that you can smell. As we fully embrace Fall, we do so in sweatshirts and light jackets. The feel of a campfire on your face (and backside) is so welcomed. Iced tea consumption goes down and cider, both cold and hot, increases. For some reason, I don't drink hot chocolate during the previous two seasons, but I sure do make up for during Fall and Winter. Oh, and Thanksgiving, don't get my started. I love to eat and all that I need is a reason.

Speaking of Winter, this season holds my favorite holiday, Christmas (my birthday as well, but His is greater)! Coats, boots, and 4-wheel drive are the order of the day. Going outside is always an adventure. I'm old enough that shoveling snow and cleaning off vehicles it's something that I can do anytime of the day (read retired), but snow still brings out my inner child.

By the end of Winter, I'm ready for Spring once more. Why do we always seem to get a snow storm when I'm ready for the daffodils to pop up...? I guess it makes me appreciate the coming Spring that much more.

Ok, backed against a wall, I'd have to go with Autumn as my favorite season. Cooler days, campfires, Halloween, Thanksgiving, [Christmas season], and all of the decorations that go with each.

favorite season

winter / Love for it to snow everything looks soo pure. untouched snow is beautiful

My favorite season

My favorite season is fall or autumn the only season with 2 names when leaves are falling and changing color it starts to cool down I love the cool weather I come from new England where its beautiful in the fall.

Any season but winter

Lived all my life in northerly climes. Retired to southerly climes. Wish I had done this 20 years ago :)

Summer and Spring

Summer and spring are my favorite seasons; I love the warm weather of spring, and also, my birthday's in the summer! (August 5)

Happy fall y'all

what I love the most about fall is everything! I love decorating my porch, raking leaves and the beautiful color of the trees, pumpkins and warm cider too. We live really close to a 100 acre park and the smell of the campfires in the air is something to remind me fall is here!

Definitely Fall

The change from hot summer to cool fall is the best. It brings back memories of being in high school going to football games and having parties around a bon fire. The smell of dead leaves brings back so many childhood memories out in the yard playing. And you cant forget Halloween! The best holiday of all!!!


I like all the seasons, but I particularly love summer firstly, then good ole spring, can’t forget fall, with fresh crisp air, yes indeed. But when it comes to winter it sure finds a way to where out its welcome.


I live in New York but I'm from Miami. I miss the sunshine all year long.

"Four Seasons"

Good mornin all at 'The' Old Farmer's Almanac

Being originally from southern New Brunswick, Canada I was brought into this world in late Autumn and my siblings are all 1st. generation 'city slickers,' My mum / father all hail from the countryside about 40 miles due north of the big city of Moncton! Farm territory, hunting, fishing, trapping and lumbering! Spent a heck of alot of time on my Grandparents farm which was in my mum's family since approx. 1800 owned by the Stevens! My grandfather being a Spencer! As with some of the contributors, I enjoy all seasons and have settled my sentiment in that manner of speaking, but if I was nudged a wee bit I'd say WINTER! Oh, why? Well it's truly the survival season and a lot around the farm reflects all year what one has to do to prepare for it! It has a super blessing of bringing the coldest of cold and this wipes the earth clean of all it's tesitude of diseases and for this one miracle alone I cherish winter!

In closing, it's so wonderful to have such a enriched process of this format to cherish & share the insightful thoughts your supporters bring and beautify your legacy! Have a super winter, hot chocolate, warm cider and a wee dram of what ale's the spirit!

Fraternally all,
N. F. Bryant
Toronto, On. Can.

Thank you

The Editors's picture

Thank you, N.F. Bryant from Toronto! We very much enjoyed reading about your life on the farm, your tribute to winter, and your positivity! 

I love the spring, its feel

I love the spring, its feel good time, because all the trees a d plants start to bud andbloom pit, everything comes back to life again, iove that all the beauty Round us ,

Favorite season

I like weather that ranges from the 60's to middle 80's with no strong wind. And I don't like winter very much but it is Wyoming. So I probably like the middle to late spring and early summer weather the best for my favorite season. If I had a favorite presipitation I would take the rain over snow. I like longer daylight, but don't like the bugs that come out in the spring and summer.


Cute article! Love the seasons :)


I have a love for all seasons. Winter for its icy beauty and quiet calm. Spring for its renewal of our spirits. Summer for its playfulness. And fall for its humbling gratitude of what mother earth has given us.

Spring for the tress starting

Spring for the tress starting to bud. Summer because it's warmer.. Fall for the beautiful colors of the trees.

Love them all

I live in NE so I love them all. I would be bored with just 1 or 2. Each season brings a new way of looking at the world. My problem is that I would like more time to enjoy each one of them.


Amazing explanation on our Seasons, all four are my favourite, do they support each other for the greater good-oh what a mighty God we serve!

All the best 24/7!

Best regards,



Amen ! Well said Michael

My favorite season is Winter

I love the winter months most of all because of the cold. The winter is more romantic, peaceful, the attitude of people is calm and caring, there’s just more love in the air.

Favorite season

Love summer! Love the longer hours of daylight. The warm sunshine. Beach days, blooming flowers! Love everything about summer!