Indian Summer: What, Why, and When?

What Is an Indian Summer?

November 3, 2020
Fall Road

In the fall, it seems that almost any warm day is referred to by most people as an “Indian summer.” And while their error is certainly not of the world-shaking variety, they are, for the most part, mistaken. Find out what a real Indian summer is!

What Is an Indian Summer?

Here are the criteria for a true Indian summer:

  • As well as being warm, the atmosphere during Indian summer is hazy or smoky, there is no wind, the barometer is standing high, and the nights are clear and chilly.
  • A moving, cool, shallow polar air mass is converting into a deep, warm, stagnant anticyclone (high pressure) system, which has the effect of causing the haze and large swing in temperature between day and night.
  • The time of occurrence is important: The warm days must follow a spell of cold weather or a good hard frost, but also be before first snowfall.
  • The conditions described above also must occur between St. Martin’s Day (November 11) and November 20. For over 200 years, The Old Farmer’s Almanac has adhered to the saying, “If All Saints’ (November 1) brings out winter, St. Martin’s brings out Indian summer.”

We rather enjoy this description written by Sandy Griswold for the Omaha Sunday World-Herald in November 1922:

I am enabled to say, however, that the characteristics of the season, when it appears in all its glory, are a mild and genial temperature, gentle southwestern breezes, unusual brightness of the sun, extreme brilliancy of the moon, a clear, blue sky; sometimes half hidden by a veil of gray haze; daybreaks redder than the splotch on the blackbird’s wing, and sunsets laden with golden fleeces, the wooded valleys aglow with the fires of richly tinted leaves, still clinging to the listless limbs, or lying where they have fallen….

Indian Summer

Why Is it Called an “Indian Summer”?

In parts of Europe, a similar phenomenon is known as an “Old Wives’ Summer” or “St. Martin’s Summer,” but how did the term “Indian summer” come to be? There are many theories.

Some say the term comes from Algonquian Native Americans located in what is now the northeastern United States, who believed that the condition was caused by a warm wind sent from the court of their southwestern god, Cautantowwit (“great spirit”).

Similarly, another origin states that Native Americans would routinely use this brief period of warm fall weather to gather a final round of supplies before winter’s hold set in.

Yet another possible origin involves European settlers in New England. Each year they would welcome the arrival of a cold wintry weather in late October when they could leave their stockades unarmed. But then came a time when it would suddenly turn warm again, and the Native Americans would decide to have one more go at the settlers. “Indian summer,” the settlers called it.

Watch a video from Almanac Editor-in-Chief Judson Hale about the origin of Indian Summer.

Indian Summer Recipes

Try our delicious Indian Summer Applesauce or Indian Pudding on your next Indian summer day.

Are you experiencing Indian summer conditions in your area? Let us know in the comments below!


The 1985 Old Farmer's Almanac


Reader Comments

Leave a Comment

Indian Summers;

Thanks for this great story Ron; That November 11th started as an unseasonably beautiful autumn day; duck hunters were out in force on the Mississippi River & the ducks kept coming in from the West. Those hunters were havin' a field day as more & more ducks flew into the river valley. Those hunters didn't realize all those ducks were fleeing a monstrous storm front approaching from the West. When that storm front arrived on the Mississippi none of them were dressed for the violent change in weather. I agree with the Indian and canoe analogy; I have learned to predict certain weather patterns based on Leaf falling patterns in Autumn;

Indian Summer;

I surmise Indian Summer was the time of the year the American Indians would begin to gather Acorns + Beechnuts for Winter Storage; (I think they got the idea from the Squirrels and Chipmunks); I think I found some wild gooseberries today coincidentally here in Connecticut.

Indian Summer

Indian Summer is here in Aurora, CO. Beautiful warm days and very chilly nights. It has been this way since the hard freeze last week.

Indian Summer

October 8, 2017 - Tulsa, OK. - feels like Indian Summer - 70's and 80's for daytime highs and 40's and 50's at night.

Indian summer

We've had a few nights of below freezing in Montrose, CO but today the sun was out and warm. So our Indian summer is starting.

Indian summer in northern Indiana

I wonder if we are experiencing an indian summer. A few weeks ago it got down to the low 60s. We didn't have a hard frost but it did seem like it was going to start being cold. Now in October we are having 80 degree days and 50-60 degrees at night.

Indian Summer in New England

I would say here in New England(New Hampshire), we are having an Indian Summer. We have not had a cold spell, but some towns have had a few frosty mornings.
September 24 - 90 degrees, overnight in the low 60's.
September 25 - high 90's, overnight in the 60's.
September 26 - low 90's, overnight 65 degrees.

Indian Summer

I live in Michigan in the south East corner of the state, in Petersburg, near the Ohio border. I believe that we are experiencing Indian Summer right now. In the past few weeks it was nice cool weather now it is so sweltering hot we can hardly go out in it. I always remember my mom telling us that it was Indian Summer the second week after we went back to school in the fall September and that would be over in late October as a matter of fact around Halloween.

Indian Summer

The weather has definitely been hot where I live also, the degrees have been in the 90's. First day of Fall 91, Second day of Fall 93, Third day of Fall 95, Fourth day of Fall 94, and the Fifth day of Fall 91

Southern Indian Summer

Unlike the North, our Indian Summer comes in late Spring and tell us, roughly, how hot our actual Summer will be.

Indian Summer

Believe we are now experiencing our Indian Summer as we had three killing frosts (lows in low 20s) and today's high will be a gorgeous and balmy near 70 with tomorrow - Friday's high to be low 70s! This morning we also had dense fog. This year's Indian Summer in Lancaster, OH, will be short-lived as Saturday, our high temps are dropping to low 40s and we won't be seeing these wonderful balmy temps again for a long time!

had hard frost here and now

had hard frost here and now is suppose to be in the high 60's and low 70's this week . So Indian summer in N E Indiana

My wife got scolded (by a

My wife got scolded (by a snooty know it all) while on a hike for using the expression "Indian Summer" as the guy said it is offensive and related to the old offensive phrase "Indian Giver". I don't believe it, but has anyone else been told this is offensive to use?

Indian Summer

I used the term this week as we are currently getting snowed out in September, and I mentioned I look forward to the Indian Summer. The twenty somethings smirked at each other as though I had used a racial slur, and I chalked it up to ignorance of this generation that has pretty much had the use of the English language cut out of their curriculum in school.

Indian Summer

This has never been a slander to any native American. They still refer to it as their Indian Summer as well. The younger generation has been manipulated into thinking everything is about a slur or a stab at someone else. It's not. I too look forward to my Indian Summers, and when it doesn't happen, that's when I go on vacation ;)

Re: whether the term Indian Summer is politically incorrect/ off

Being native American myself, with ancestors dating as far back as 1896, I say it's not at all offensive to myself. However, I can't speak for the rest of society whom seems to be offended over everything in the name of political correctness these days. I say, use the term if you're not uncomfortable doing so while not being racist towards us "savage native injuns". Haha. Guy's obviously a DICK, and more than likely white. As such, has no absolute "right" to be offended, and needs to get over himself, in all honesty. Although I certainly don't refer to myself as Indian personally. Why? Indians are from India, Native Americans by birth, being indigenous to North America. However, I do use the term myself to describe an unnaturally long growing season in Northern New England. 'Nuff said.

My wife got scolded

No, but if I did I would simply tell him he is wrong and why does he believe it is an insult and not an honor to have something named after you? There is nothing derogatory about this time of year.

snooty hikers

must have been the same guy that told me I'll have to stop wearing my Redskins Football Club hat on Cedar Run Trail in S.N.P. He was standing awfully close to a cliff.

Beautiful autumn here on Long

Beautiful autumn here on Long Island. But no red or orange in the trees. Perhaps due to the incredible heat this summer? The leaves are all yellow, with few exceptions. Usually when the green fades with decreasing chlorophyll production, we get scarlets, clarets, tangerines... not this year. Only the Japanese maples are red. Even the Bradford and Chanticleer pears which generally can be counted upon for vivid colour are almost a muddy reddish=brown, like the dregs of old wine. VERY old wine. But the temperatures are pleasant, and if we got a really hot day, I could still consider a (brief!) swim in LI Sound.

I have always heard Indian

I have always heard Indian Summer are the two weeks of warm weather after the first hard frost.

We have had beautiful fall

We have had beautiful fall weather this year in the Ozarks. Our temperatures have been above normal. Our forecast for this weekend is showing the first below 40 degree temperature since last winter. Our leaves did not seem to have quite the colors they usually have in my particular area which is in North Central Arkansas.

In North Central Ohio the

In North Central Ohio the leaves are having such vibrant colors. There has already been frost, cold weather, especially at night, with very mild temperatures (60 degrees) occurring now. This is our INDIAN SUMMER now. Thanks for sharing your information.

We've had a beautiful autumn

We've had a beautiful autumn here in Wisconsin, but with no hard frost I don't consider it an Indian Summer. I agree with the almanac that after a hard frost (and all the leaves are on the ground) a spell of warm weather is considered "Indian Summer".

An Indian Summer begins today

An Indian Summer begins today (Nov 4) in Saskatchewan. Temps are forecasted to be 10 to 15•C above normal, with temps near freezing at night. Air pressure is high, around 1023 mb. Also, no precip in sight. Going to enjoy it while it lasts!

It was 80 degrees in

It was 80 degrees in Summitville Indiana today and supposed to reach upper 70's tomorrow. I believe we are experiencing an Indian Summer here as well.

Although it's not November

Although it's not November yet, 80 degrees three days before Halloween is rather warm for West Des Moines, IA this time of year.

In Lexington, Kentucky we are

In Lexington, Kentucky we are experiencing an Indian Summer right now and for the next few days. It is 80 degrees today which breaks a record for the highest historical temperature.

Indian Summer

We are experiencing an very warm Indian Summer in Santa Fe, NM

Indian Summer

We experienced what is described as Indian Summer here in Washington DC last week. I am now reading a book where the story takes place in Paris and there is s reference to Indian Summer. I thought Indian Summer was only an American experience. So I decided to investigate the origin and meaning of the phrase

Indian summer in New England!

It's an Indian summer here in Boston that's about to come to a close. It's shocking, though it comes every year and being a true New Englander I know that odd temperatures at odd times of the year are bound to happen. Last winter, there was a day in February where I was walking around in a t-shirt!