Leadville Trail 100
Race Day Weather
Cool start, warming finish
Runners will face a start at 46°F, gradually warming to 67°F by the finish. Wind will be light at 5 mph, with headwinds affecting runners from miles 1 to 12 and again in segments following mile 27. With humidity at 52% and a dew point of 38°F, hydration should be prioritized as temperatures rise, especially in the valley. Adjust pacing early to manage the climbs and prepare for warmer conditions in the latter stages.
This course climbs 2,247 ft to its high point and back, so we look at it at 2 points, not just the start line. In a typical year, at 9:00/mi, you start at 46° and finish around 6:59 PM in 67°.
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Race Info
The Leadville Trail 100 Run (aka The Race Across The Sky or the LT100) is an ultramarathon held annually on rugged trails and dirt roads near Leadville, Colorado, through the heart of the Rocky Mountains. First run in 1983, the race course climbs and descends 15,600 feet (4,800 m), with elevations ranging from 9,200 to 12,620 feet (2,800–3,850 m). In most years, fewer than half the starters complete the race within the 30-hour time limit. Wikipedia
