Late November in Philadelphia sits in a genuinely favorable window for marathon racing — cool enough to keep pace times honest, without regularly tipping into the kind of extreme cold or heat that wrecks a training block's worth of work. That said, favorable on average hides a fair amount of year-to-year swing, and the honest answer to what race-day weather will be like is that it depends more than most runners expect on which year they happen to run.

What a typical race morning feels like

The start line sits well below where most runners will be comfortable standing around — cold enough that gloves and a throwaway layer are standard advice here, not overkill. Conditions typically warm modestly as the morning goes on, so the temperature at the gun is rarely the temperature you'll be racing in by the time you're deep into Fairmount Park or out on Kelly Drive. The facts card above this guide has the specific seasonal averages on file for this race; what's useful here is the shape of a typical morning, not the exact number.

How much it varies year to year

Averages smooth over what is actually a fairly wide range of race-day experiences. Some editions have opened closer to freezing with a hard, biting wind; others have started mild enough that runners shed layers within the first mile and never looked back. Rain shows up in a minority of years — most editions stay dry throughout — but when it does arrive it tends to come paired with wind rather than on its own, which is a tougher combination than either factor alone. The practical takeaway is to build a race-week weather check into your plan rather than trusting the seasonal average to describe the specific morning you'll be running in.

Wind and humidity: the hidden factors

Temperature gets most of the attention, but two other factors shape how the weather actually feels on this course. The first is wind: the long out-and-back along Kelly Drive runs directly beside the Schuylkill River with little shelter, so a breezy morning turns an otherwise flat, fast stretch into a genuine grind, especially on the return leg if the wind has shifted to a headwind. The second is humidity, and here Philadelphia has a real advantage — race-morning dew points here tend to run drier than at many other fall marathons, which matters more for how hard the effort feels than the raw temperature reading does. A cool, dry morning is a meaningfully easier experience than a cool, damp one at the same thermometer reading.

How to dress for it

• Plan on a cold start regardless of the forecast — throwaway layers (an old long-sleeve, a bin bag, cheap gloves) that you can shed in the first few miles are standard practice here.
• Check the forecast in race week, not just the seasonal average, given how much year-to-year variation this race has seen.
• Treat wind as a separate variable from temperature, especially on the exposed Kelly Drive and Manayunk out-and-back — a calm cold morning and a windy one at the same temperature are not the same race.
• Don't over-dress for the finish just because the start feels cold — most editions warm up enough by late morning that extra layers become dead weight by the second half.

The bottom line

Philadelphia's late-November date gives it a real climate advantage over summer and early-fall marathons — cool temperatures and comparatively low humidity are conditions distance runners generally race well in. But generally favorable is a description of the average, not a guarantee for your specific race morning. Check the forecast close to race day, dress in layers you're willing to discard, and treat wind along the river as its own variable worth planning for separately from whatever the temperature reads.

How conditions compare to other fall races

Compared with early-fall marathons that still carry summer humidity, or Midwest and Great Lakes races that can swing more unpredictably, Philadelphia's late-November slot is about as close to a reliable cold-weather window as the East Coast marathon calendar offers. That reliability is relative, not absolute — plenty of runners have raced here in a cold snap or a wet morning — but the odds favor conditions that let you race close to your training paces rather than fight the weather for it.

None of this replaces checking an actual forecast. Weather services become genuinely useful in the final week before the race, once a longer-range pattern is reliable rather than speculative. Treat anything you read months out, including seasonal averages like the ones on this page, as a planning baseline rather than a promise about your specific race morning.