Autumnal Equinox 2020: The First Day of Fall

Facts & Folklore About the Fall Equinox

September 18, 2020
Autumn in Colorado

In 2020, the autumnal equinox—also called the September equinox or fall equinox—arrives on Tuesday, September 22. Fall begins in the Northern Hemisphere and spring begins in the Southern Hemisphere. Read about the signs of fall and the ways we mark the approaching equinox. 

Autumn has caught us in our summer wear.
–Philip Larkin, British poet (192286)

When Is the Autumnal Equinox?

The fall equinox arrives on Tuesday, September 22, 2020, at 9:31 A.M. EDT. The equinox occurs at the same moment worldwide.

Autumnal Equinox Dates and Times

Year Autumnal Equinox (Northern Hemisphere)
2020 Tuesday, September 22
2021 Wednesday, September 22
2022 Thursday, September 22
2023 Friday, September 22

What Is the Autumnal Equinox?

Autumn days come quickly, like the running of a hound on the moor.
Irish proverb

The autumnal equinox—also called the September or fall equinox—is the astronomical start of the fall season in the Northern Hemisphere and of the spring season in the Southern Hemisphere.

What Is an Equinox?

The word “equinox” comes from Latin aequus, meaning “equal,” and nox, “night.” On the equinox, day and night are roughly equal in length. (See more about this below.)

During the equinox, the Sun crosses what we call the “celestial equator”—an imaginary extension of Earth’s equator line into space. The equinox occurs precisely when the Sun’s center passes through this line. When the Sun crosses the equator from north to south, this marks the autumnal equinox; when it crosses from south to north, this marks the vernal equinox.

After the autumnal equinox, the Sun begins to rise later and nightfall comes sooner. This ends with the December solstice, when days start to grow longer and nights shorter.

Fall bridge

Fall Weather

It is the summer’s great last heat,
It is the fall’s first chill: They meet.

–Sarah Morgan Bryan Piatt

Another definition of fall is “nights of below-freezing temperatures combined with days of temperatures below 70 degrees Fahrenheit (21°C)”. From here on out, the temperatures begin to drop.

Will fall bring crisp, cool weather—or, unseasonably warm weather? It depends on where you live! See our 2020 Fall Weather Forecast.

Find 12 months of long-range weather predictions in the new Old Farmer’s Almanac!

Fall Foliage

Note that fall foliage isn’t due to current weather conditions. This is a common misconception. Leaves change color because of the amount of daylight and photosynthesis. Learn more about autumn leaves.

Japanese maple leaf in fall

Fall Equinox FAQs

Q: Are Day and Night Perfectly Equal on the Equinox?

A:  Some say that during an equinox, day and night is equal. Well, not exactly. It depends on where you live.

On the equinox, the center of the Sun is indeed above the horizon for 12 hours. However, “sunrise” is said to begin when the upper edge of the Sun’s disk becomes visible above the horizon (which happens a bit before the center rises) and ends when the entire Sun has set. In this case, daylight is still a bit longer than nighttime. 

Not only that, but the Sun is actually visible when it is below the horizon, as Earth’s atmosphere refracts the Sun’s rays and bends them in an arc over the horizon. Yes, you can see the Sun before the edge actually reaches the horizon! This causes daylight to be longer than 12 hours as well.

However, they are very close to equal (the total lengths may differ by only a few minutes). 

Did you know our rise/set tool now provides day length? In Dublin, New Hampshire, USA—home of The Old Farmer’s Almanac—our day length on the equinox is 12:08 hours.

See our Sunrise/set calculator for day length in YOUR area.

Q: Is the Autumnal Equinox Really the First Day of Fall?

A: Based on the astronomical definition of seasons, yes, the autumnal equinox does mark the first day of fall (in the Northern Hemisphere). However, according to the meteorological definition of seasons, which is based on temperature cycles and the Gregorian calendar, the first day of fall is September 1.

Q: Can You Balance An Egg On the Equinox?

A: There’s an old-wife’s tale that you can stand an egg on its end of the equinox. Well, yes, it’s true (and fun to try). But it’s not only on the equinox. See more about equinox facts from Almanac astronomer, Bob Berman.

autumn woods

Signs of Fall

What are your local signs of fall? In many regions of the Northern Hemisphere, the landscape silently explodes with vibrant colors of red, yellow, and orange. The leaves begin to drop off the trees, providing endless hours of jumping into leaf piles for kids and raking them back up for parents!

Trees snapping and cracking in the autumn indicate dry weather.

Fall also brings some wonderful holidays, including Halloween and Thanksgiving, which carry us through the season until temperatures begin to drop, nights begin to get longer, and all the woodland critters start storing up for the long haul of winter

And don’t forget about the end of Daylight Saving Time, when we “fall” back, setting our clocks back one hour and regaining an hour of precious sleep!

Plants and trees are slowing down, as sunlight decreases, to get ready for the colder season ahead. In the garden, asters and chrysanthemums bloom beautifully as orange pumpkins and corn mazes abound.

Football season is warming up and so is sweater weather.

Also notice the arc of the Sun across the sky each day as it starts shifting south. Birds and butterflies migrate along with the path of our Sun!

Of course, you can you can easily notice the later dawns and earlier sunsets. See our sunrise/set tool for your area!

Purple Aster
Aster flowers

Ancient Autumn Traditions 

The fall equinox has been a day of celebration for cultures since ancient days. People tracked the transitions of the Earth’s journeys around the Sun.

  • At Machu Picchu in Peru, an ancient stone monument called Intihuatana—which means “Hitching Post of the Sun”—serves as a solar clock to mark the dates of the equinoxes and solstices.  
  • In Mexico, the Mayans built a giant pyramid called Chichen Itza. On the equinoxes, it looks as if a snake made of light slithers down the pyramid’s steps.
  • In England, Stonehenge was also built with the equinoxes and solstices in mind.

See Five Ancient Sites Aligned With the Equinoxes and Solstices.

Enjoy Autumn!

Wishing a colorful, cool, cozy autumn to all our Almanac readers. Tell us your favorite things about the fall season below!

To learn more about all four seasons and see when they begin, see First Day of Seasons.


Reader Comments

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My grandfather always said in the south east area of the united states "when pecan trees bud there will be no more frost !"

Thumping on the Roof Top

Thumping on the Roof Top

Though there be no sign in the leaves, Fall lets us know it's coming around- -the-been by the syncopation of acorns falling all around the yard and imitating hail on our roof. We have two large White Oaks, one in the front and the other in the back yard that start giving away a bonanza of fruit in the first week of September. The critters, squirrels and chipmunks respond like it was an invitation to a ball. They're actively eating, burying, hoarding, and chasing each other around as some kind of instinctual dance rite sponsored by Mother Nature herself. So in the Capitol Region of NY, before all the other undeniable aspects of Fall sets in, the oak trees and their acorns are first to announce the annual change of the season.

I assume twilight lasts about

I assume twilight lasts about the same for both the spring and fall equinoxes, and that summer twilight would be shorter than winter because in the summer the sun sets more perpendicular to the horizon than the winter.

Good theory??

"Come little Leavy", said the

"Come little Leavy", said the Wind one day, "Come over the meadow with me and play. Put on your dressy of red and gold, the summer's gone and the days grow cold."


Soon the little leaves heard the winds loud call and they tumbling one and all. Over brown meadows they danced and flew singing a little happy song they knew. Dancing and whirling the little leaves went, winter had called them and they were content. Soon fast asleep in their earthly beds ,the snow made a coverlet over their heads . My mom sang this to me years ago. Thanks for bringing back a great memory.

Ahh The first day of

Ahh The first day of fall..LOVE IT!And the Stores are already decorating for CHRISTMAS!Rediculous!

I love all the seasons

Fall starts tomorrow, no more jet skiing, riding my harley onto late evenings, BBQs, and so on.. Tomorrow I change with the seasons, dark sunglasses, leather boots, scarves, and the occasional cigar, fall is a time where I can reflect on mothers nature dark intimate beauty, I wish I could go on, good night every body.

i am going great on the fall

i am going great on the fall season but my allergies are bothering me much more all of the time thanks for the fall weather!!halloween is coming up thank goodness my birthday will be soon!!!!

What does autumn (which came

What does autumn (which came from the Latin autumnus) mean in English?

The English word "autumn,"

The Editors's picture

The English word "autumn," meaning the season between summer and winter, or the third season of the year, is thought to trace back to the Latin autumnus. However, no one really knows how the Latin word developed. The Oxford English dictionary says the Latin autumnus was also written as auctumnus and is "of doubtful etymology." Several etymology sources mention the word could possibly have come from augeo or auctum, meaning "to increase" or augment. Some say the word may have ultimately come from an Etruscan word. Autumnus may be interpreted as "season of increase."

Welcome Autumn - Let leaves

Welcome Autumn - Let leaves Fall , but I stand up and admire . I fall asleep earlier , and rise up as Sun rises .

The Autumn (Fall) is all

The Autumn (Fall) is all dressed up for the Ball and I'am going to dance <3 <3 <3

I live for autumn - my

I live for autumn - my favorite season! Every year I look forward to the sun shining brightly in our windows - but at a different angle than it did all summer. I also look forward to the bright clear days opposed to the very hazy days of our summer. These two signs tell me autumn is knocking at our door - and I welcome it!

Hello! Without a telescope,

Hello! Without a telescope, what do you see that harvest
moon worshippers can see between September 23rd, the Autumnal Equinox, and All Hallows EVE?

At 66 years of age, I am

At 66 years of age, I am between Boston, MA & C.Bus, OH., so I see a lot of different weather patterns. I have noticed, New England area getting LESS RAINS, past few years.

"The pleasure that is in

"The pleasure that is in sorrow", a poet has written, "is sweeter than the pleasure of pleasure itself." Hence the beauty of the fall of the year, and hence our particular delight in the spectacle it presents to our senses. It's a spectacle of decline, deterioration, and bereavement -- a melancholy spectacle. We respond to it for that very reason. We love the fall because of it's melancholy, not in spite of it.

The sweet sadness of the year's end doesn't set in until most of the autumn leaves are gone from the trees. The autumn colors are too bright and too busy to have the effect, though they point to it. It's when the leaves are brown, and few, and the branches and the trunks of the trees are gray that they begin to produce the emotional tone of this season, the tone of loss. The low skies of November, the dun ponds and frozen brooks, are a dark setting.

But although the season has a sorrowful character, it isn't a depressing time. On the contrary: The atmosphere of these last weeks before winter comes is the antithesis of depression. The senses -- the feelings -- become more receptive, educated by the stripped-down, impoverished look of the land. Maybe the last leaves, long dead, that hang on the trees are few in number, but you consider each one of them. Maybe the subdued little salt-and-pepper birds of November don't know many songs, but they have a companionable presence the brighter summer birds lack. In a part of the year that witholds the occasions for high spirits, the pleasure that we take is the pleasure of reflection, and it's keen, because it goes down deep.

Thanks, John, for the

Thanks, John, for the reflection on autumn. Those with eyes to see and a heart to feel will resonate with your observation that each season presents object lessons our own lives must pass through. Really appreciate your thoughts and invite you to share mine on Thanks again and best wishes.

Is it true that the more rain

Is it true that the more rain you get during Spring and Summer the greater the Fall colors will be?

For spectacular fall color,

The Editors's picture

For spectacular fall color, trees should have healthy growing conditions for spring and summer. In general, a warm, wet spring followed by a moderate summer. Then in fall, they need sunny, dry, warm days followed by dry, cool nights with temperatures above freezing. Other factors that affect color include species, plant health, genetics, shade, and soil moisture and fertility. A dry summer, for example, may cause the leaves to drop too early before they change. Too much rain may cause health problems for the tree, which may also affect fall color.

Two points: I still don't

Two points: I still don't know which month Autumn officially starts - and getting down this page to enter my comment was hard work

I agree about this page not

I agree about this page not specifying the month of the Autumnal Equinox!

In 2015, the autumnal equinox

The Editors's picture

In 2015, the autumnal equinox falls on September 23 at 4:21 A.M. (ET). 

I love Autumn. It is my

I love Autumn. It is my favorite season. To me it is the time the trees show off their finest leaves and and the nicest smells of wood smoke, and crisp fall air. Leaves to rake and jump in with your child or grand children, and then a harvest dinner of winter squash, corn, chicken,and apple pie.Parties,popcorn balls,candy apples bonfires, and friends. I'm anticipating it with a quiet excitement. :-D

Me too! It seems people

Me too! It seems people around me want summer to never end but I love the fresh, crispness in the Fall air and being able to wear jeans again!

Born this time of year. I

Born this time of year. I appreciate it more as an adult. Yes, I can hardly wait. Hosting a bonfire on HollowEve!

My favorite season is autumn.

My favorite season is autumn. I love the crisp air in the morning. I love to see the harvest moon lighting my pastures. The barely there outline of my horses breath when they breath. I don't mind the shorter days, I like the dark. I love Autumn. For some reason it makes me feel calm and cozy. The smell of firewood, the softness of a big fuzzy blanket around me as I sip a hot cup of coffee on my porch.....Ugh, I can't wait. Unfortunately, here in Gettysburg our Autumns only last a short while. I would love to live where it feels like fall most of the year.

I love autumn too. Hot drinks

I love autumn too. Hot drinks fire place going. Wearing sweaters scarfs and leggings. Cuddling on couch watching movies with my family. I wish I had a porch that would be beautiful. You have horses as well, I bet it's beautiful where u live. I'm from California. I replied to your comment because your description sounds so beautiful. Thank you for sharing, enjoy your autumn

Thank you.. I hope you

Thank you.. I hope you enjoy yours as well ! sorry misspelled breathe

it literally just turned fall

it literally just turned fall today (sept 23) and i already feel a HUGE difference. like literally yesterday it felt like summer and today it feels like winter. is the weather supposed to change that fast on the specific date? just feels kinda weird that the weather would change like that ON the specific date.