F^3 Lake Half Marathon
F^3 Lake Half Marathon race day weather
Cold start, crosswinds expected
Runners will face temperatures starting at 25°F and only rising to 27°F by the finish. With a maximum wind speed of 12 mph from the WSW, crosswinds will impact the gently rolling course throughout. Hydration remains crucial, but runners should focus on maintaining pacing and consider wearing layers to combat the cold, especially during the pre-race warm-up.
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F^3 Lake Half Marathon route and elevation
The F^3 Lake Half Marathon course has about 394 ft (120 m) of climbing and 413 ft (126 m) of descent, a net drop of about 19 ft (6 m). It is flatter than 72% of the half marathon courses racecast.io has mapped, measured by what the hills cost in time. The hardest mile is mile 2, with 105 ft (32 m) of climbing.
Biggest climbs
- Miles 1.1 to 1.3: climbs about 80 ft (25 m).
- Miles 12.4 to 12.8: climbs about 80 ft (24 m).
What the hills cost
- 1:45 on a flat course is about 1:45:15 here (15 seconds slower).
- 2:00 on a flat course is about 2:00:15 here (15 seconds slower).
- 2:15 on a flat course is about 2:15:15 here (15 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 1:45, 2:00 or 2:15 finish
| Mile | Climb | Descent | 1:45 | 2:00 | 2:15 |
|---|---|---|---|---|---|
| 1 | 38 ft | 51 ft | 7:56 | 9:04 | 10:12 |
| 2 | 105 ft | 91 ft | 8:07 | 9:17 | 10:26 |
| 3 | 32 ft | 32 ft | 8:00 | 9:09 | 10:18 |
| 4 | 39 ft | 33 ft | 8:03 | 9:12 | 10:21 |
| 5 | 23 ft | 28 ft | 7:59 | 9:07 | 10:15 |
| 6 | 40 ft | 46 ft | 7:59 | 9:07 | 10:16 |
| 7 | 29 ft | 18 ft | 8:05 | 9:14 | 10:24 |
| 8 | 15 ft | 30 ft | 7:56 | 9:05 | 10:12 |
| 9 | 41 ft | 30 ft | 8:06 | 9:14 | 10:24 |
| 10 | 35 ft | 32 ft | 8:01 | 9:10 | 10:19 |
| 11 | 42 ft | 43 ft | 8:00 | 9:09 | 10:17 |
| 12 | 36 ft | 43 ft | 7:58 | 9:06 | 10:14 |
| 13 | 84 ft | 100 ft | 7:56 | 9:04 | 10:12 |
| Last 0.1 | 4 ft | 3 ft | 0:54 | 1:02 | 1:10 |
Explore the F^3 Lake Half Marathon course with the weather and your pace along the route, or compare it with other races.
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About the F^3 Lake Half Marathon
The F^3 Lake Half Marathon & 5k is a winter race on Chicago's Lakefront Trail, run in late January or early February and starting beside Soldier Field. The USATF-certified half marathon heads briefly north, then turns south for an out-and-back on the trail, with splits every 5 km and three aid stations that each get passed twice. Runners meet in Soldier Field's United Club before the race, start in self-seeded waves about every 90 seconds, and finish with a medal and a hoodie. The 2025 edition set the course record, 1:05:13 by Chandler Gibbens.
