Jack and Jills Downhill Marathon (Saturday) Half Marathon
Race Day Weather
Comfortable temps, big temp swing
Mild 51°F temps at gun time mean comfortable early miles without overheating risk. Temps will climb significantly to 71°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing. Moderate humidity at 66% is worth noting for effort level, especially in later miles.
Pace Calculator
Enter a finish time to see what race day does to it.
Get forecast alerts for Jack and Jills Downhill Marathon (Saturday) Half Marathon
We'll text or email you when the forecast shifts — so you can adjust gear, pacing, and strategy. Max one per day.
Get your personalized Jack and Jills Downhill Marathon (Saturday) Half Marathon race plan
A mile-by-mile breakdown of where your time goes, weather-adjusted splits, fueling timeline with aid stations, packing checklist, carb tracker, spectator guide, all built around your goal and race-day conditions.
Race Info
The Saturday half marathon at Jack & Jill's Downhill Marathon & Half runs 13.1 miles on the Palouse to Cascades State Park Trail, from the Hyak Trailhead near Snoqualmie Pass to Garcia, near North Bend. It covers the downhill second half of the marathon course and enters the unlit 2.4-mile Snoqualmie Tunnel near the start, so runners carry a headlamp or flashlight. The surface is smooth, hard-packed gravel on a former railroad grade. The course is USATF-certified, and the same half marathon is run again on Sunday.
