Autumnal Equinox 2019: The First Day of Fall

Facts & Folklore About Fall

September 20, 2019
Autumnal Equinox - Fall Road
Pixabay

In 2019, the autumnal equinox—also called the September equinox—is Monday. On this day, fall begins in the Northern Hemisphere and spring begins in the Southern Hemisphere. Wondering why it’s called an equinox? Here’s all you need to know.

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

When is the Autumnal Equinox?

In 2019, the autumnal equinox occurs on Monday, September 23 at 07:50 UTC. The equinox occurs at the same moment worldwide; your clock time depends on your time zone (3:50 a.m. EDT, 2:50 a.m. CDT, 1:50 a.m. MDT and 12:50 a.m. PDT).

Year Autumnal Equinox (Northern Hemisphere)
2019 Monday, September 23
2020 Tuesday, September 22
2021 Wednesday, September 22
2022 Thursday, 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 fall in the Northern Hemisphere and of spring 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 terms of length.

During the equinox, the Sun crosses what we call the “celestial equator”—an imaginary extension into space of Earth’s equator line. 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 is rising 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! Find out the forecast for your area in The 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: No. Even on the equinox, day and night aren’t perfectly equal! However, they are very close to equal (the lengths may be off by only a few minutes). Why does this happen?

It depends where you live. On the equinox, the center of the Sun is 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 longer than 12 hours.

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 actually see the Sun before the edge actually reaches the horizon! This causes daylight to be longer than 12 hour as well.

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

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, but it’s not just on the equinox. Still, it’s a bit of fun. Try it yourself! 

See more fun facts and myths about the old, misunderstood equinox from Almanac astronomer, Bob Berman.

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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.

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Reader Comments

Leave a Comment

How Do I Know It's Fall?

I know it's fall when the black walnut tree drops its green balls! We collect them and give them to our squirrels and chipmunks and they have a ball biting into them, running with them, storing them. The red squirrel is the quickest to grab them! : )

equal day and night

Wouldn't the day be slightly longer than the night, because of the diameter of the Sun? If it was a point source it would be exact, but it is not a point source.

day length

The Editors's picture

Daylight is longer than nighttime at the actual equinox, in part because the Sun is a disk, not a dot, and of the definition of sunrise and sunset, and therefore, length of day. Daytime is defined as beginning when the upper edge of the Sun reaches the horizon (which happens a bit before the center rises), and it doesn’t end until the entire Sun has set. So, that adds a little time (a few minutes) to daytime. If the Sun were a point, then we wouldn’t have those extra minutes. Also, because of our atmosphere, which bends light, the Sun appears a bit higher than it actually is. Therefore, it makes sunrise occur a little earlier and sunset a little later, which also adds a bit of time. How much time depends on latitude. It the Sun were a point, and we didn’t have atmosphere, then daytime and nighttime at the equinoxes would be 12 hours each.

For any day, you can find the rise and set times of the Sun, Moon, and planets, as well as day length, for your area, at this page:
http://www.almanac.com/astronomy/rise/

Hope this helps!

Autumn is coming

The darker early mornings that were once day. Especially around 6:30-7A.M.! Midday and early evening times seem more of a fall look in the sky as well. Some days, I smell the Autumn in the air around this time frame and it has that Autumn look and feel. Big giveaway is when the Georgia National Fair arrives in Perry, GA!! :0) Hope these helped or maybe someone else can relate to these signs I see and feel. Don't quote me on these! Just going by my OWN opinion!

How we know Fall is coming!

We live on a National Bicentennial Farm in the Blue Ridge Mountains of Virginia. We're fairly remote where we are in Grayson County, and our farm is surrounded on all sides by mountains. Because of this, we are very attuned to nature, and wild life. The mountains make a giant calendar all around us, where we can pinpoint any time of year by where the sun sets and rises, and at night mark the change in the position of the Milky Way. Also because of the mountains around us, there's an abundance of wildlife, and we can mark the coming of Fall by their changes as well. The crickets drown out the dawn chorus of the birds as Summer winds down, and as Fall approaches, they go all day and night as opposed to just at night. The second most prominent wildlife change is that the Screech Owls become far more vocal at night, when I hear those, I know Fall is on it's way! The cows become fussier because it's usually dry here at the end of Summer, and there's less choice grass for them to eat, meaning they have to be moved more often. Finally, the mountains themselves begin to change. Long before the leaves themselves turn, the mountains go from lush uniform green, to a very faint, but discernible undertone of different colors barely visible under the green of the leaves. Fall and Winter are my favorite times of year here, and I look for these signs every year to let me know that my first favorite season is on its way! I'm listening to those crickets right now!!

Beautiful description

Love your essay! Your description of the mountains being your calendar is very charming! Enjoy the upcoming beauty!

Your essay

The most beautiful feeling I've ever had just became words from your fingertips. Thank you.

Beautiful

Please keep writing about all the seasons on your farm! It sounds like the perfect place to be to witness their changes, and you have a wonderful way of describing them. Thank you.

How We Know Fall is Coming by M.S. Greene

You my friend, have a Greene thumb for writing.

Wonderful!

Sounds like you are living in Eden! Your descriptions are so evocative, I could just about smell the air where you are. You didn't need to attach a picture as you painted such perfect pictures in words, but I wish you had! Please share more! I'd like to think you feel pretty blessed to be on your place. Lovely, just lovely. Thank you.

when does winter start

when does winter 2016 start in South Florida?

When does winter start?

The Editors's picture

In the Northern Hemisphere, winter begins on December 21, 5:44 A.M. EDT. See our page about First Day of Winter here: http://www.almanac.com/content/first-day-winter-winter-solstice   Note that how you define the first day of winter depends on whether you are referring to the astronomical or meteorological winter. Most calendars (including ours) refer to the astronomical seasons which are a result of the Earth’s axis and orbit around the sun.

Winter

That's a good one Yarissa! Winter in South Florida. They have summer and a really long spring.

transplant trees/knock out roses

When can you trans-plant knock-out roses, boxwood trees and crept myrtle trees?
please advise,
monika

spring

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."

Poem/song

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.

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