When Can You Start Wearing Fall Clothes? The 60-Degree Green Light Never Arrives in Four American Cities
The fall clothes are bought, the feeds have moved on to knitwear, and it was 91 degrees in New York this month. The two rules the internet keeps repeating both come with a date attached, so I pulled thirty years of federal weather normals for fourteen cities and checked what those dates actually feel like.
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The knitwear went up on the walls this month. Between August 1 and August 19, the daily high at Central Park averaged 84.6 degrees and one of those days hit 91. Atlanta averaged 92.1. Boston, which likes to pretend it’s already October, averaged 84.9 and topped out at 94.
That’s the gap the autocomplete is standing in. People type when can you start wearing fall clothes because the clothes are already bought, hanging up, and unwearable in the actual air outside.
Two answers circulate. Who What Wear’s version is a thermometer rule: “If it’s going to stay a consistently cool 60 degrees all day long, then you’ve got the green light to rock your favorite fall ankle booties, oversize autumn sweaters, and statement coats.” The other is the calendar: September 22, the autumn equinox, because it’s technically fall.
Both are checkable.
NOAA publishes daily climate normals, the 1991 to 2020 average of what each day of the year actually does at a given station, and they’re free to anyone who wants them. We haven’t worn anything to test this; what follows is a calendar audit, not a wear test.
When can you start wearing fall clothes?
Fall clothes become wearable after sunset weeks before they become wearable at noon. In New York the normal overnight low slips under 60 degrees on September 19, while the normal daytime high doesn’t do the same until October 28, a gap of thirty-nine days in a single city, and every city below has some version of that gap sitting inside its autumn.
| City | Normal high on Sept 22 | High first drops below 70F | High first drops below 60F | Low first drops below 60F |
|---|---|---|---|---|
| Minneapolis | 69.1 | Sept 20 | Oct 13 | Aug 28 |
| Chicago | 72.4 | Sept 28 | Oct 23 | Sept 2 |
| Boston | 70.2 | Sept 23 | Oct 20 | Sept 9 |
| Seattle | 68.7 | Sept 19 | Oct 15 | before Aug 1 |
| Denver | 75.9 | Oct 5 | Oct 30 | Aug 2 |
| New York | 72.9 | Sept 30 | Oct 28 | Sept 19 |
| Washington DC | 77.2 | Oct 11 | Nov 11 | Sept 23 |
| Atlanta | 80.2 | Oct 27 | Nov 26 | Sept 30 |
| San Francisco | 73.5 | Oct 20 | Nov 27 | before Aug 1 |
| Dallas | 86.1 | Nov 9 | Dec 3 | Oct 6 |
| Los Angeles | 82.2 | Nov 27 | never | Oct 10 |
| Houston | 88.2 | Nov 23 | never | Oct 20 |
| Phoenix | 97.9 | Nov 28 | never | Oct 29 |
| Miami | 88.9 | never | never | never |
Source: NOAA daily climate normals, 1991 to 2020, one first-order station per city, our own read of the August through December series. “Never” means it doesn’t happen before December 31. Two rows need a warning label: Seattle and San Francisco start the window already below their own thresholds, because their summers don’t get warm enough to cross back, so those cells describe a mild place rather than an early autumn.
Does the 60-degree rule work?
The 60-degree green light is later than almost anyone expects, and in four major cities it’s never. Minneapolis is the first to qualify, on October 13. Chicago waits until October 23, New York until October 28, Washington until November 11, Atlanta until November 26, Dallas until December 3. In Los Angeles, Houston, Phoenix and Miami the normal daily high does not fall below 60 at any point in the fall.
Read that against what the rule licenses. Ankle boots, oversize sweaters and statement coats, all held behind a gate that opens in New York four days before Halloween and never opens at all across the Los Angeles, Houston, Phoenix and Miami metros.
As written, it’s a description of late autumn wearing a September headline.
Is the autumn equinox when fall clothes start?
The equinox is a poor wardrobe signal: on September 22 the normal high is 69 degrees or warmer in all fourteen cities, from 69.1 in Minneapolis to 97.9 in Phoenix. Nine of the fourteen are still above 72. Phoenix on the first day of fall normally runs 97.9, which is 14 degrees hotter than Minneapolis on the Fourth of July.
What the equinox does mark is light. Sunset in New York comes roughly an hour earlier by September 22 than it does in mid-August, the low that night normally sits near 58, and that combination is the actual thing that changes in September. Which is why the answer here is a time of day and not a date.
What about the UK?
London’s autumn runs the same evening-first pattern, compressed by about a month. At Heathrow the 1991 to 2020 mean daily maximum is 68.4F in September and 60.5F in October, while the mean daily minimum is already 52.9F in September and 47.8F in October, which puts a British September afternoon at roughly the temperature of a New York early October afternoon and a British September night at sweater weather it has been holding all along.
One caveat on that row: the UK figures are Met Office monthly means for a single station, not daily normals, so they answer “which month” rather than “which date.” They’re not directly comparable to the American columns above, and I’m not going to pretend otherwise.
What should you actually buy in late August?
One evening layer covers the entire transition in most of the country. From the last week of August through most of October, the pattern in every northern city on the list is the same: an afternoon that doesn’t want a sweater and a 7 p.m. that does. A cardigan you can carry, a light knit, an unlined jacket. That’s the whole gap.
The pieces the August roundups push hardest are the ones the calendar says you’ll use last. Wool coats, chunky knits and tall boots are October and November items in the north and, in four big metros, essentially never daytime items at all. They’re also the items that get cheapest exactly when they become wearable, which we charted for sweaters and again for boots.
Buying them now means paying the year’s highest price for the privilege of storing them.
There’s a real counter-argument and it isn’t the weather. Sizes go first, and the thing you want in October may be gone by then, which is a genuine trade and one we’ve put actual numbers on. But it’s a stock argument, not a “you can wear this now” argument, and the two get blended together every August by people with something to sell.
One last note on the limits here. Normals are averages, not forecasts, and any given week can run ten degrees off the line in either direction. A cold snap on September 8 is a perfectly good reason to wear the cardigan on September 8. What the numbers rule out is only the reverse move: treating a date on a calendar, or a rule you read in a headline, as the thing that decides.
The cardigan gets worn. Around dusk, sometime in the next three weeks, and not because a headline said it was allowed.