When Do the Seasons Start in 2021?

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

January 1, 2021
Spring, Summer, Fall, Winter 360

When do all of the four seasons—spring, summer, fall, and winter—start and end? Find your equinox and solstice dates for 2021 and 2022—plus, learn 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, while the meteorological start date is based on the 12-month calendar and the annual temperature cycle. See below for a more in-depth explanation.

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.

Definition of “Season”

What exactly is a “season”? 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.

Because an almanac is an astronomical “calendar of the heavens,” The Old Farmer’s Almanac follows the astronomical definition of the seasons.

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 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

Leave a Comment

Australia vs Canada

When it's winter in Canada it's summer in Australia. So does Canada follow Australia's spring/summer or does Australia follow Canada's fall/winter. Curious, food for thought!

That image!!

Can you please tell me... Who is the photographer/designer of the image at the top of this page (with the circular sky - showing all the seasons)?

seasons picture

The Editors's picture

Hi Adam, It’s a really great image, isn’t it? This particular image is “stock,” and free to use if you wish. Enjoy, and thanks for asking!  Your OFA editors.

How to make your own using your own picture(s)

Hi, recent coincidental find is an android app that came recommended to me called "FX Pro" by "Tiny Planet". I you've access to an Android device and Google Play, simply search the Play Store for, "Tiny Planet FX Pro", you'll know you've found it by the similar styled app icon.

Enjoy Adam!. Also my thanks and wishing a prosperous New Year to all at 'The Old Farmers Almanac'.


general comment

I find this site helpful and the comments sometimes informative but definitely entertaining:))

Seasons start and end dates for Fort Walton Beach, Floida

What I would like to know is can I lookup this information using my zip code to get more accurate dates ?

start of seasons

The Editors's picture

Hi Vicki, For 2016, the autumnal equinox and the vernal equinox are the the same dates across North America, however, the exact time your will shift according to your time zone. You may find this page helpful for a time and date calculator: http://www.timeanddate.com/calendar/seasons.html  All the best, the OFA editors

First Days of the Seasons

When perusing the above illustration of the Earth's rotation, I was wondering if the 3-degree change in the position of the Earth's axis, caused by the massive Pacific earthquake responsible for the disaster of Fukushima, had been factored in. This natural occurrence has been sited as another significant reason for the climate and weather changes we're experiencing, especially in Alaska and other northern regions. Also, the currents of the Pacific have now succeeded in carrying the radiation-contaminated waters leaking from the Fukushima disaster full circle, contributing to rising ocean surface temperatures and irreversible pollution.

Not really

There most certainly hasn't been a sudden 3 degree change in the earth's axis (whatever that might mean). Nor has the radiation leak made any difference to water temperature - it was truly a tiny leak, and even if all the energy of the whole power station were used to heat the oceans, it would make zero measurable difference.

Max Impact

Thank you! Know your source...all kinds of crazy predictions causing massive spending... Things are heating up because the veil of God is being lifted...be more worried about that

The beginning points of the seasons.

Dear Old Farmer's Almanac:

How could you get this one wrong? The solstices and equinoxes are the mid points of the seasons, not the beginning of the seasons. Spring most often begins on February 2. The vernal equinox, on 3/21 is the mid point of Spring. Summer begins on May 1. You know, May day. Midsummer, it seems Shakespeare knew better, is the Summer solstice, the mid point of Summer. Please get this right.

Season starts

The Editors's picture

Hi, Kevin, You are among those who champion the traditional season starts—on the Quarter Days (the solstices and equinoxes) and the corresponding Cross-Quarter Days (the mid-points between the Quarter Days). We have addressed this on the Almanac pages and we will bring this information to the Web site. However, it is not likely to change the predominant view; the current seasonal calendar has been too long and deeply engrained in the public seasonal psyche to change many hearts and minds. So we will continue to acknowledge also these familiar dates and bring the others to (greater) light. We salute you for recognizing this distinction!

How to determine the beginning and end of each season?

Hi Kevin, I have always been curious about knowing the beginning and ending of the four seasons of the year. Actually, is there a way to calculate the seasons? Here in Guyana we have the wet and dry 'seasons'. And as such, I do not know how to determine the beginning and ending of each season. I must say I fully endorse your views about the seasons herein. Therefore, kindly provide me an answer for my question. Thanks.

In those famous words of Old

In those famous words of Old Hill - what difference does it make?

What difference

A winter does not end in the same year it starts, so the winter of 2014 would be followed by the spring of 2015. The winter of 2015 would not be followed by the spring of 2015.
It makes a difference in historical matters. If you say a certain relative died in the winter of ????, a listener could assume the date of death was a full year different from the truth.

"The winter of...'

Why do some people call this winter, that started in December of 2015, "the winter of 2016"?
Surely the winter of 2016 will start in December of 2016.
We don't call the Christmas celebrated in 2015 "the Christmas of 2016".


We seem to be talking apples and oranges. Comparing different things. Weather and seasons are similar to apples and orange comparisons. The ecliptic and the heavenly bodies decide seasons. Hot/cold dry/wet decide weather

good page

Fab page and web site!


That's a Springtime Miracle I can accept!


And in His image He made Man, who is the one responsible for writing, copying and editing The Book; and the errors passed along in new editions with men and women responsible for viewing the book through filters of misconception and ignorance, fear and hate. By the way, I heard the universe does not revolve around Rome - the NASA depiction... I guess I could see how the foolish could think it is correct. Matter of perspective. Happy Festive. Go be kind with someone with a different perspective. I am inclined to believe in Axial Tilt. I don't get seasons where I live, just the season of Summer and the brief - non-summer with non-summer being shorter every year.
Please copy and paste this message.


The milestone of creation is the cornerstone of colophone of districts.

Bloody darkness'

No sun - I hate it!

Says the one whose name is

Says the one whose name is 'bloody *darkness*'.


please create a season calendar for adding to Google calendar

We were always taught Summer-

We were always taught
Summer- first week of June - first week Sept
Fall- fall second week Sept- second week Nov
Winter- third week Nov- fourth week Feb
Spring- first week March- first week June

Unfortunately your family

Unfortunately your family taught you their generational learnings rather than actual facts for what the seasons are.

When winter actually occurs.

Kdh1969 is more accurate in stating when the seasons actually occur "than your actual facts for what the seasons are". If you lived in the upper Midwest, you would know that from year in and year out experience. Rob in South Dakota

How come it doesn't list the

How come it doesn't list the Southern Hemisphere?

The Old Farmer's Almanac is

The Editors's picture

The Old Farmer's Almanac is North America's most popular annual publication. Our tools, tables, and content across astronomy and the Moon, calendar, weather forecasts, planting dates, etc., may be relevant to many (and we welcome all), however, the content is written for the U.S. and Canadian readers of our publication; the free companion Web site provides this information as a courtesy.

Solstices and Equinoxes are

Solstices and Equinoxes are the same date and time for the entire Earth.

You could try to call the June Solstice as the "Northmost Solstice" and the September Equinox as the "South-moving Equinox", to simply describe the Sun's apparent motion.