The Trailbreaker

Waukesha, WI, USA · April 4, 2027
partly-cloudy-day36°·44° high·Breezy·Dry
10
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Race Day Weather

partly-cloudy-day
36°at start
45° high
Breezy
Dry

Cold start — layer up, moderate wind

Runners will start in chilly 36°F conditions — dress in layers for the corral and plan to shed early. Temperatures rising to 45°F through the course will gradually increase perceived effort in the second half. Moderate winds around 13mph may affect pacing on open sections of the course. Moderate humidity at 69% is worth noting for effort level, especially in later miles.

Race day forecast available in 180 days
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Pace Calculator

Distance: 26.2mi
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Race Info

The Trailbreaker is Waukesha's home grown running event and has been held annually since 1993. This Waukesha tradition initially consisted of a Marathon, Half-Marathon, and 5K Run/Walk. Both Marathon courses are certified by the USATF and may provide qualifying credentials for other races. We are excited to once again offer a 10K event at the Trailbreaker. The Trailbreaker originally was the brainchild of three running colleagues (amigos). Since 2009, the Park Foundation of Waukesha, Inc. (PFW Inc.), has organized and hosted this annual event as a fundraiser for the enhancement of city parks, trails, recreation programs and the urban forest. Source

Race weekend

Sunday, April 4
Marathon (26.2 mi)
Half Marathon (13.1 mi)
10K (6.2 mi)
5K (3.1 mi)
Area Map

Course Map

FAQ

When is the 2027 The Trailbreaker?

The 2027 The Trailbreaker will be held on Sunday April 4, 2027.

Is the The Trailbreaker a Boston Marathon Qualifier?

Yes, the The Trailbreaker is an official Boston Marathon qualifier.

What will the weather be like for the 2027 The Trailbreaker?

The forecast calls for a high of 48°F and a low of 36°F with a 13% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.

Historical Weather

Based on 2 years of data
Avg Temp
44°F
L:35° H:52°
RunScore
10
Conditions
Rain Freq
0%
0 of 2 yrs
Wind9mph
Dew23°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore
2026
partly-cloudy-day
40°/59°-
10
2025
partly-cloudy-day
30°/44°-
10