In 90 days · Sat, Jan 30, 2027
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Saturday, January 30th, 2027
1410 Special Olympics Drive, Chicago IL
Half · 5K
19–31°F · some rain risk
See last 10 years
On this date: rain 2 of the last 10 years
2026
8–21°F
dry
2025
27–47°F
rain
2024
32–40°F
dry
2023
5–18°F
dry
2022
8–29°F
dry
2021
27–34°F
rain
2020
29–35°F
dry
2019
-22–-8°F
dry
2018
15–32°F
dry
2017
16–33°F
dry
Best months to race in Illinois →
About this race
The 18th Annual F^3 Lake Half Marathon & 5k is Chicago's Original Winter Half Marathon. Each year, thousands of runners flock to this community-built event, gathering in the warmth of Soldier Field's United Club before tackling wind & weather along a lakefront course that features splits every 5km. A must for anyone preparing for a spring marathon or just resolving to stay fit throughout the new year. F^3 sold out in 2016-2020 and 2023-present.
Every registrant will once again receive one of our great hoodies and a medal! We will return to the warm confines of Soldier Field's United Club! The UC opens at 8 a.m. Gear check is available. The half marathon starts at 10:01 a.m. and consists of self-seeded waves in quick succession. The 5k is scheduled for 10:29 a.m. Courses close at 1:30 p.m.
After the race, head to Weathermark Tavern for the afterparty! 1503 S. Michigan Ave. Free participant photos are always uploaded to flashframe.io
Course map
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