Charles River Marathon
Charles River Marathon race day weather
Cool conditions, adjust for wind
Runners will face a temperature starting at 45°F and peaking at 52°F, with an average humidity of 64% and a dew point of 35°F. Wind from the NW at 18 mph, gusting to 30 mph, will create a steady headwind throughout. Competitors should consider pacing adjustments to account for wind resistance and stay hydrated as they navigate these conditions.
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Charles River Marathon route and elevation
The Charles River Marathon course has about 468 ft (143 m) of climbing and 464 ft (141 m) of descent, and finishes near the elevation it starts. It is flatter than 68% of the marathon courses racecast.io has mapped, measured by what the hills cost in time. It has no steep miles: no mile climbs more than 40 ft (12 m).
What the hills cost
- 3:30 on a flat course is about 3:30:25 here (25 seconds slower).
- 4:00 on a flat course is about 4:00:30 here (30 seconds slower).
- 4:30 on a flat course is about 4:30:30 here (30 seconds slower).
Hills only, priced mile by mile on the course map. The pace calculator above adds the race-day weather.
Even-effort splits for a 3:30, 4:00 or 4:30 finish
| Mile | Climb | Descent | 3:30 | 4:00 | 4:30 |
|---|---|---|---|---|---|
| 1 | 21 ft | 33 ft | 7:56 | 9:04 | 10:12 |
| 2 | 33 ft | 23 ft | 8:05 | 9:14 | 10:23 |
| 3 | 37 ft | 32 ft | 8:01 | 9:10 | 10:20 |
| 4 | 32 ft | 44 ft | 7:57 | 9:05 | 10:12 |
| 5 | 35 ft | 22 ft | 8:05 | 9:15 | 10:24 |
| 6 | 28 ft | 36 ft | 7:58 | 9:05 | 10:14 |
| 7 | 33 ft | 31 ft | 8:00 | 9:10 | 10:18 |
| 8 | 32 ft | 28 ft | 8:02 | 9:10 | 10:19 |
| 9 | 30 ft | 41 ft | 7:56 | 9:05 | 10:13 |
| 10 | 34 ft | 29 ft | 8:02 | 9:10 | 10:20 |
| 11 | 28 ft | 31 ft | 7:59 | 9:07 | 10:15 |
| 12 | 30 ft | 36 ft | 7:58 | 9:07 | 10:14 |
| 13 | 39 ft | 22 ft | 8:08 | 9:17 | 10:28 |
| 14 | 32 ft | 40 ft | 7:57 | 9:06 | 10:13 |
| 15 | 31 ft | 23 ft | 8:04 | 9:13 | 10:22 |
| 16 | 33 ft | 34 ft | 7:59 | 9:07 | 10:16 |
| 17 | 29 ft | 44 ft | 7:56 | 9:04 | 10:12 |
| 18 | 39 ft | 21 ft | 8:08 | 9:18 | 10:28 |
| 19 | 23 ft | 38 ft | 7:56 | 9:04 | 10:12 |
| 20 | 34 ft | 28 ft | 8:02 | 9:11 | 10:20 |
| 21 | 31 ft | 30 ft | 8:00 | 9:08 | 10:17 |
| 22 | 38 ft | 41 ft | 7:59 | 9:07 | 10:15 |
| 23 | 29 ft | 27 ft | 8:00 | 9:09 | 10:18 |
| 24 | 28 ft | 36 ft | 7:57 | 9:06 | 10:14 |
| 25 | 31 ft | 31 ft | 8:00 | 9:08 | 10:16 |
| 26 | 40 ft | 21 ft | 8:09 | 9:18 | 10:28 |
| Last 0.2 | 6 ft | 9 ft | 1:46 | 2:02 | 2:17 |
Explore the Charles River Marathon course with the weather and your pace along the route, or compare it with other races.
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About the Charles River Marathon
The Charles River Marathon offers a flat, fast, and USATF-certified 42.2-kilometer course along Boston's scenic Charles River, starting and finishing at Herter Park. Runners complete ten laps on a 2.6-mile loop, with over 49% of finishers qualifying for the Boston Marathon in recent years. This event combines competitive racing with a supportive atmosphere, featuring live DJ music and a focus on fundraising for cancer research.
