Jack and Jill's Downhill Marathon

Jack and Jill's Downhill Marathon 2026 Course Analysis

Jack and Jill's Downhill Marathon is a full marathon held in Washington, United States of America, scheduled for Sunday 17 May 2026. The course is run on trail surface with 119m of total elevation gain, reaching a maximum altitude of 786m above sea level. For registration and full race details, visit the official Jack and Jill's Downhill Marathon website.

Elevation Profile

With 119m of elevation gain, this is a moderately undulating course. The route ranges from 517m to 786m above sea level (269m total range). While not completely flat, the elevation changes are manageable for most runners and shouldn't significantly impact pacing strategy.

Expected Race Day Weather

Based on historical weather data for May, the expected race day conditions are as follows. Hot conditions are expected, with temperatures between 18°C and 33°C. Heat is one of the biggest performance factors in marathon running — research shows that for every degree above 15°C, marathon times slow by approximately 1-2%. Extra hydration and a conservative start are strongly recommended. There is a low chance of rain (15%), so dry conditions are likely.

Surface Type: Trail

Jack and Jill's Downhill Marathon is a trail race, meaning the course includes unpaved surfaces such as dirt, gravel, or forest paths. Trail surfaces are inherently slower than road courses due to uneven footing, technical sections, and often steeper gradients. Trail-specific shoes with good grip are recommended, and runners should expect a finish time 10-20% slower than their equivalent road marathon time.

How Difficult Is Jack and Jill's Downhill Marathon?

Our difficulty rating for Jack and Jill's Downhill Marathon is calculated using a model that combines elevation gain, temperature impact, and surface type. Use the difficulty calculator above to enter your target finish time and see exactly how many minutes this course would add or subtract compared to a perfectly flat, cool, road-based marathon. Faster runners and slower runners are affected differently by the same course conditions, so the difficulty is personalised to your pace.

Looking for an easier marathon or a tougher challenge? You can also compare Jack and Jill's Downhill Marathon against other marathons to find the right race for your goals.