Diablo Trail Marathon
Race Day Weather
Cool start, warming finish
Runners will face a cool start at 56°F, maintaining that temperature through the first seven miles before warming to 67°F at the finish. Winds will be light, peaking at 8 mph, creating crosswinds in the early miles and shifting to a tailwind around mile 18. With moderate elevation changes, runners should adjust their pace conservatively, especially during the climbs from miles 1 to 7 and 16 to 21.
This course climbs 3,182 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 56° and finish around 11:55 AM in 67°.
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