Autumnal Equinox 2019: The First Day of Fall

Facts & Folklore About Fall

November 6, 2018
Autumnal Equinox - Fall Road
Pixabay

In 2019, the autumnal equinox—also called the September equinox—will arrive on September 23 in North America. Wondering why it’s called an equinox? 

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

When is the Autumnal Equinox?

Although the equinox happens at the same moment worldwide, your clock times will depend on your time zone.

Year Autumnal Equinox (Northern Hemisphere)
2018 Saturday, September 22
2019 Monday, September 23
2020 Tuesday, 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 spring in the Southern Hemisphere.

Why is it called an equinox? The word comes from the Latin aequus, meaning “equal” and nox, meaning “night.” 

During the equinox, the Sun crosses what we call the “celestial equator.” Imagine a line that marks the equator on Earth extending up into the sky above the equator from north to south. Earth’s two hemispheres receive the Sun’s rays about equally. The Sun is overhead at noon as seen from the equator, so at this point, the amount of nighttime and daytime (sunlight) are roughly equal to each other.

See the sunrise and sunset for YOUR location.

After the autumnal equinox, the nights will get longer and the days shorter until the December solstice near Christmas.

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 misperception. 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, “sunrises” 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 provide 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 it’s a bit of fun.  Try it! 

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

autumnal-equinox-fall.jpg

Nature’s Signs of Fall

What are you 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!

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 then don’t forget about the end of Daylight Saving Time when you “fall” back, setting your clocks back one hour and regaining an hour of sleep.

Plants and trees are slowing down, as sunlight decreases. 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, Stonehedge 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

Leave a Comment

I love the change of seasons.

I love the change of seasons. When my grandson was 4 yrs he asked why the trees changed. Trying to explaine so a 4 yr. old could undeersta, I told him in the fall trees are puting on thier pj's, in the winter they were asleep, and in the spring when they woke up, they were green again.
I've really noticed the birds flocking togeather. Fall is on the way

The first signs of fall I see

The first signs of fall I see every year is wolf spiders and wood spiders moving into my house. I love fall, but absolutely hate spiders. There's been four meet untimely deaths so far, there'll be 50 more at least before the snowflakes fall.

what the hell!! U need to go

what the hell!! U need to go to the store and by some raid bombs and set them off in ur house every two weeks or once a month all through out the fall and winter season mate. All of them will die :-D

Spiders are very beneficial

Spiders are very beneficial to our enviromnent, I never hurt one...

No way, not me and spiders.

No way, not me and spiders. I visited orlando,fl., and came back with mrsa from a spiderbite

Watching a web glitter in the

Watching a web glitter in the fall morning sunlight and bounce with a gentle breeze should be enough to make anyone appreciate the skill of this creature who even lives in Kings palaces--let's give'm there space.

I'm with you on the spiders.

I'm with you on the spiders. I don't want to hurt any piece of life, but the spiders simply cannot live in my house with me in it too! Grandson Jack and I noticed quite a few huge yellow and black spiders in the individual webs outside this week. They're coming closer . . .

The poplars around here (West

The poplars around here (West Virginia) are always the first to turn, followed by maples. The poplars have been yellowing and losing leaves for about 3 weeks or better. Temps all summer have been really High, but its beginning to feel more normal now with highs in the 70's and lower 80's, lows from the upper 40's to lower 60's. And than goodness the grass growth has slowed :)

A fall nip was in the air in

A fall nip was in the air in the flatwoods of Fla this past weekend. What a blessing it was. Great working in the yard and pasture. Really enjoy getting our fall garden ready to plant.

Yes, fall is coming. The

Yes, fall is coming. The first sign typically noticed in the northeast is the migration of the Nighthawk. They are already on the move.

Here where I live in MA the

Here where I live in MA the trees are still green and I still hear the peepers at night as well as cicada's during the day. We have has cooler nights (upper 50"s) and the days haven't been out of the 70's all week. My window looks out over the woods and I am looking forward to seeing the color change in the leaves.

in neo the fall transition

in neo the fall transition seems to be a month early.but I do enjoy it

Fall is coming

Fall is coming

Here where I live in MA I

Here where I live in MA I still am hearing the peepers and cicada's. The leaves are still green. The only thing that is telling me the season is changing is it's been in the 50's at night which is nice to sleep in. The days haven't been out of the 70's for the past week.

Here in Southern Ontario, the

Here in Southern Ontario, the days are getting slightly cooler, and the nights are definitely lots cooler!

I love everything about OFA

I love everything about OFA and Autumn! I just wish we could have 4 months of Autumn temps and colors, unfortunately we get to look forward to temps over 100+ for another month here Central AZ:(

Will Autumn ever get here?!

Here in the South (Memphis, Tennessee) Summer begins at Easter and lasts until Halloween. This year, we went from April to August in about two or two and a half weeks' time. It was 75, and THEN IT WAS 95.... The crape myrtles that don't normally bloom until late July bloomed in early May. I cannot wait until Thanksgiving.... I am already so tired of heat indexes and Code Orange ozone alerts and excessive heat warnings. :(

in Missouri, nights are

in Missouri, nights are becoming a little cooler, and heat-stressed trees are starting to turn.

Now this is some very

Now this is some very interesting information. I really learned a lot by reading these questions and answers. Thank you so much for publishing this educational information. There is much here to absorb.

I absolutely love it when

I absolutely love it when fall comes. It is my favorite time of year. I cannot wait to break out my sweaters and hoodies. Thank you for this report and I can't wait to read more from you.

 

 

If we see the legalism of an casino online anytime soon I will wager at the slot machines but only the ones that are honest.

I agree Maryjane ,it`s my

I agree Maryjane ,it`s my favorite time of yr too,I love the smell in the air ,the beauty of the changing leaves ,and the cool nights........my cats love it too!!

Even though I am in Florida,

Even though I am in Florida, I notice the mornings being just a tad cooler. By cooler I mean not so humid! But, it is nice. In a few weeks when the evening weather cools, too, my cats also love it. They get almost as frisky as their mama!

I see flocks of migrating

I see flocks of migrating birds wheeling overhead and sometimes dropping down onto the pond to rest for a bit; the male hummers have left; and the air feels crisper somehow.

even in texas at some point

even in texas at some point you can catch a scent of autumn on the breeze. of course the heat here does not end until way later, being from kansas i have a keen sense of the air. autumn is the best time of year!

I wish that would happen in

I wish that would happen in Houston nowadays ... we are facing another week of 100+ F.

Fall

Me, too. And summer has only just begun.... I can't wait until Fall.

I wish that would happen in

I wish that would happen in Houston nowadays ... we are facing another week of 100+ F.

We live in Houston,

We live in Houston, too....but i see a cool front on the horizon Monday the 26th, let's hope and pray! take care neighbor!

Yeah I see a cool front also

Yeah I see a cool front also it will only be in the upper 90"s instead of 100 what a cool down!

It is 76 degrees right now in

It is 76 degrees right now in Fort Worth. Thank goodness summer is over for us. High of 83 today.

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