Autumnal Equinox 2018: First Day of Fall

When is the First Day of Fall 2018?

Autumnal Equinox - Fall Road

The autumnal equinox or September equinox next falls on Saturday, September 22, 2018. Here’s everything you need to know about the equinox and signs of the equinox in nature.

When is the Autumnal Equinox?

Specifically, the Northern Hemisphere marks the autumnal equinox on Friday, September 22, 2018, at exactly 9:54 P.M. EDT.  

Year Autumnal Equinox (Northern Hemisphere)
2017 Friday, September 22
2018 Saturday, September 22
2019 Monday, September 23

What is the Autumnal Equinox?

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

The word equinox comes from the Latin aequus (equal) and nox (night). 

During the equinox, the Sun crosses what we call the “celestial equator” (just imagine the line that marks the equator on Earth extending up into the sky) from north to south.

Earth’s two hemispheres are receiving the Sun’s rays about equally. The Sun is overhead at noon as seen from the equator. At this point, the amount of nighttime and daytime (sunlight) are roughly equal to each other.

Another definition of fall is nights of below-freezing temperatures combined with days of temperatures below 70 degrees Fahrenheit. From here on out, the temperatures begin to drop and the days start to get shorter than the nights.

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

–Sarah Morgan Bryan Piatt

What’s in store for your winter weather? Order your copy of The Old Farmer’s Almanac!

Japanese maple leaf in fall

Why Aren’t Days and Nights Equal?

Nights and days actually aren’t perfectly equal on the equinox, as in 12 hours of daylight and 12 hours of nighttime. The split may be off by a few minutes. Why does this happen?

It depends on where you live. On the autumnal and vernal equinoxes, the very center of the Sun sets just 12 hours after it rises. But the day begins 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. 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.

According to our former Almanac astronomer, George Greenstein, “If the Sun were to shrink to a star-like point and we lived in a world without air, the spring and fall equinoxes would truly have ‘equal nights.’”

Does the Sun rise due east and set west at the equinox? See more odd equinox facts from astronomer Bob Berman!

What Falling Leaves Indicate

There’s an old weather proverb that states, “If autumn leaves are slow to fall, prepare for a cold winter.” This means that leaves that hang onto the tree indicate a colder winter to come. Or, perhaps you just haven’t had enough windy days! But look on the bright side—you get to look at the beautiful autumn foliage for a little bit longer. Learn why autumn leaves change color.


Signs of Fall

In many regions of North America, 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!

Plants and trees are slowing down, as sunlight decreases. However, in the garden, asters and chrysanthemums bloom beautifully as orange pumpkins and corn mazes abound. Baseball season hits the homestretch, while football season is just warming up.

Halloween and Thanksgiving 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

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

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!

How do you know that fall is coming? Share your ideas in the comments below!

Purple Aster
New England Aster.

Autumn Folklore and Verse

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

Trees snapping and cracking in the autumn indicate dry weather.

If, in the fall of the leaves in October, many of them wither on the boughs and hang there, it betokens a frosty winter and much snow.

Spring rain damps;
Autumn rain soaks.

Of autumn’s wine, now drink your fill; the frost’s on the pumpkin, and snow’s on the hill.
The Old Farmer’s Almanac, 1993

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

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

Reader Comments

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Fall lasts 4 months, and Christmas lasts 3 weeks. I decorate for fall. The nativity is enough for Christmas.
"September" by Helen Hunt Jackson
1 The golden-rod is yellow;
2 The corn is turning brown;
3 The trees in apple orchards
4 With fruit are bending down.

5 The gentian's bluest fringes
6 Are curling in the sun;
7 In dusty pods the milkweed
8 Its hidden silk has spun.

9 The sedges flaunt their harvest,
10 In every meadow nook;
11 And asters by the brook-side
12 Make asters in the brook,

13 From dewy lanes at morning
14 The grapes' sweet odors rise;
15 At noon the roads all flutter
16 With yellow butterflies.

17 By all these lovely tokens
18 September days are here,
19 With summer's best of weather,
20 And autumn's best of cheer.

21 But none of all this beauty
22 Which floods the earth and air
23 Is unto me the secret
24 Which makes September fair.

25 'T is a thing which I remember;
26 To name it thrills me yet:
27 One day of one September
28 I never can forget.

The First day of Fall

This beautiful day will always be forever in my heart as the day I said "I do".

Outside with the changing leaves around us, my love and I became husband and wife.

We walked on a pathway of pumpkins and mums, to a floating stage of sunflowers.

Five years later and many memories made, we moved into our new home on the 22nd of September.


My Grandmother always said that it was never officially Fall until the Spider Lillies bloomed. I look for mine every year (they bloomed last week here). I think of her when I see them.

My animals tell me what kind of winter it's gonna be

When my cats and horses start getting thick coats early, I know the winter is gonna be COLD and hard. If they're slick up until Thanksgiving, I know a winter is gonna be mild.

Stink bugs! All over the

Stink bugs! All over the house. That's how I know fall is here.

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

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:

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.


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.


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?

In the Northern Hemisphere, winter begins on December 21, 5:44 A.M. EDT. See our page about First Day of Winter here:   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.


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,


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 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 .