Berlin Marathon 2026: What the Heat Cost the Field
Berlin started near 55°F and peaked at 75°F. Here is what that warmth cost a typical finisher, priced with Racecast's pace engine.
Guye Adola won the men's race in 2:02:50, and Tigst Assefa won the women's race in 2:11:04, a new course record and the third-fastest marathon ever run. The race started cool and warmed up sharply through the afternoon. This recap looks at what that warmth cost the rest of the field, and how much.
The Conditions on Race Day
The morning was mild. At 9:00 a.m. local time the air was 55°F with a dew point near 48°F. Between 10:00 and 3:00 p.m. the temperature climbed from 62°F to 75°F, and it stayed between 73 and 75°F until about 6:00 p.m. Humidity fell as the air warmed, to the mid-40s and then the mid-30s percent, so the heat came with dry air.
Sun was the other factor. Solar radiation passed 500 W/m² by noon and peaked near 620 W/m² at 2:00 p.m. There was no rain. Wind picked up through the middle of the day, reaching about 14 mph from the southeast between noon and 2:00 p.m. A breeze cools a runner, but on the stretches that face it, it also pushes back.
Racecast's race audit puts the 2026 wet-bulb globe temperature (WBGT, the heat-stress number that combines air temperature, humidity, sun and wind) at 58.1°F. The same audit's median finish for 2026 was about 4 hours 11 minutes, which it places roughly 2.5 minutes slower than the race's cool years.
How We Priced It
Racecast's pace engine takes a run's pace and its hour-by-hour weather, then works out how much slower that effort ran because of the heat, the sun and the rain. It is the same model we use for race-day pacing, run in reverse. It asks what a cool, calm day would have allowed at that effort, and reports the difference in seconds per mile.
For this recap we used the observed 2026 hourly weather for Berlin, with a mass start at 9:15 a.m. local. We priced two typical finishing paces: a 3:30 finisher at about 8:01 per mile, and a 4:30 finisher at about 10:19 per mile. Each hour of the run is priced at the pace the runner held in that hour, then weighted by how much of the hour the runner spent on the course.
Two parts of the cost are not in these numbers. Wind drag along the route and the hills both depend on the direction and grade of each stretch, and we have not priced them here. The figures below cover heat, sun and rain only.
What the Heat Cost a Typical Finisher
For the 3:30 finisher, the weather cost about 12 seconds per mile: roughly 10.4 seconds of heat and 1.7 seconds of sun. Over 26.2 miles that adds up to about 5 minutes and 20 seconds. The same effort on a cool, calm day would have run about 7:48 per mile, 13 seconds faster than the 8:01 the runner actually held.
For the 4:30 finisher, the cost was about 19.5 seconds per mile: roughly 16.7 seconds of heat and 2.8 seconds of sun. Over the full distance that is about 8 minutes and 30 seconds. This runner was still on the course at 1:45 p.m., with the temperature near 73°F and climbing toward its 75°F peak, so more of the run was spent in the heat.
The gap between the two runners is the point. A 3:30 finisher spent most of the race in the morning's cooler hours. A 4:30 finisher ran into the afternoon, the same city and the same start, but a different race.
What the Results Show
Add the two winning times together and you get 4:13:54, the second-fastest cumulative winning time in history behind Chicago 2024. The heat did not stop the front of the race from being fast. The cost lands further down the field, where most entrants live. Berlin had more than 56,000 entrants from 162 nations, and a few seconds per mile, multiplied across four or five hours of running, is the difference between the time you planned and the time you ran.
If you race Berlin, check the hourly weather for the hours you will be on the course, not just the start. The temperature at the gun is the number that gets quoted, but the temperature at your finish time is the one that shapes your last 10 kilometers.
Sources
Results and entrant count: The Running Channel, "Berlin Marathon 2026: Results, Winning Shoes & The Things You May Have Missed", published 28 September 2026.
Race-day weather: Racecast's observed hourly record for Berlin on 27 September 2026, local time (Europe/Berlin). Race audit and WBGT figures: Racecast's year-by-year Berlin audit, including 2026. The pace-cost figures come from running the Racecast pace engine on that hourly record. For the course and its history, see the Berlin Marathon race page and Berlin Marathon weather history.