The NYC Marathon Was Unseasonably Warm Again. That Spells Trouble.

The buzzy topic of conversation among New York City Marathon race volunteers in the predawn hours of Sunday morning wasn’t if a course record was going to be broken or Peres Jepchirchir’s pre-race withdrawal, but how we decided what we were going to wear.

This year, I was one of the marathon Start Village’s waste diversion and composting volunteers (on brand!), which meant setting an alarm for 2:05 a.m. to catch a bus to Staten Island in time for check-in. When I left my apartment, the temperature was a nippy 47 degrees and still dropping; my toes started to hurt from the cold during the on-site orientation and I was grateful I’d opted for a fleece base layer. But by the time my shift ended, and the last wave of runners was heading across the start line and over the Verrazano Bridge, it was around 63 degrees and I was sweating through my volunteer beanie. One of the most discarded items at my waste diversion station, up there with banana peels and spare water bottles, was unused hand warmers.

According to historic weather data kept by FindMyMarathon.com, the 2023 New York City marathon was about 5 degrees warmer this year than average. Blessedly, it was also about 11 degrees cooler than last year’s record high of 74 degrees, which caused hundreds of heat-related injuries, depleted on-course water stations, and saw runners collapsing along the five-borough route. The ideal marathon temperature, metabolically speaking, is between 52 and 54 degrees Fahrenheit (or, by some estimates, even colder), which is part of why New York’s November marathon has been such an ideal and legendary race, albeit one that can be bitterly cold at the start line. Though that might be changing.

As I’ve written before, the world’s major marathons, which are held during the shoulder seasons to optimize good running weather, are trending warmer. According to one study, the number of cities that could host an Olympic marathon safely is expected to decline by 27% by as soon as the late 21st century due to rising temperatures. Boston Marathon winning times are expected to get slower and slower as the city’s average April high temperatures continue to creep up. The New York City Marathon, which used to be held annually in October, has already been bumped back, in the 1980s, in pursuit of cooler temperatures and faster results; is there a future in which it could be bumped back again, to mid- or late-November, solely because of climate change?

Sunday’s high in the 60s ultimately didn’t impact the marathon results too dramatically; Tamirat Tola managed to set a new course record, after all. And admittedly, runners are prone to complain if it’s above 55 degrees out, as Laura Green jokes in her popular “Strava Decoded” TikTok video. But the 2023 New York City Marathon didn’t make it out of the year entirely unscathed by climate change, either: The race’s officially sanctioned 18-mile training run on Sept. 30 was canceled due to flooding from a storm that researchers said was 10% to 20% wetter than it would have been a century earlier.

As a high-intensity sport that requires traversing miles of outdoor space, road running is — and will continue to be — especially vulnerable to these sorts of shifts. This year, runners mostly lucked out with the weather. But November 2024 is another year.