Weather
Actual| Time | Temp | Dew Pt | Humidity | Wind | Conditions |
|---|---|---|---|---|---|
| Start | 46°F | 45° Ideal | 97% | 4 mph E | Clear sky |
| 8:00 AM | 48°F | 46° Ideal | 93% | 6 mph E | Clear sky |
| 9:00 AM | 53°F | 49° Ideal | 85% | 4 mph E | Clear sky |
| 10:00 AM | 58°F | 49° Ideal | 73% | 6 mph SE | Clear sky |
| 11:00 AM | 61°F | 48° Ideal | 61% | 6 mph SE | Clear sky |
| Finish | 64°F | 46° Ideal | 53% | 6 mph SE | Clear sky |
Elevation Profile
Course Stats
Mile Splits
| Mile | Grade |
|---|---|
| 1 | -0.6% |
| 2 | +0.0% |
| 3 | -0.1% |
| 4 | -0.3% |
| 5 | +0.1% |
| 6 | +0.0% |
| 7 | +0.0% |
| 8 | -0.1% |
| 9 | +0.0% |
| 10 | -0.1% |
| 11 | -0.2% |
| 12 | +0.3% |
| 13 | -0.1% |
| 14 | +0.1% |
| 15 | -0.1% |
| 16 | +0.1% |
| 17 | -0.1% |
| 18 | +0.1% |
| 19 | -0.2% |
| 20 | -0.1% |
| 21 | +0.2% |
| 22 | -0.1% |
| 23 | -0.1% |
| 24 | +0.1% |
| 25 | +0.2% |
| 26 | +0.0% |
| 27 | -0.3% |
| 28 | +0.4% |
| 29 | -0.3% |
| 30 | -0.2% |
| 31 | +0.0% |
| 32 | -0.2% |
| 33 | -0.1% |
| 34 | +0.2% |
| 35 | +0.1% |
| 36 | +0.0% |
| 37 | +0.1% |
| 38 | +0.3% |
| 39 | -0.2% |
| 40 | +0.5% |
| 41 | -0.2% |
| 42 | -0.2% |
| 43 | +0.5% |
| 44 | -0.1% |
| 45 | -0.4% |
| 46 | +0.0% |
| 47 | +0.0% |
| 48 | -0.1% |
| 49 | +0.0% |
| 50 | -1.2% |
| 51 | +1.3% |
| 52 | +0.0% |
| 53 | +0.0% |
| 54 | +0.1% |
| 55 | +0.1% |
| 56 | +0.3% |
| 57 | +0.0% |
| 58 | -0.4% |
| 59 | +0.1% |
| 60 | +0.4% |
| 61 | -0.7% |
| 62 | +0.2% |
| 63 | -0.2% |
| 64 | +0.0% |
| 65 | -0.1% |
| 66 | -0.1% |
| 67 | -0.2% |
| 68 | +0.1% |
| 69 | +0.1% |
| 70 | -0.1% |
| 71 | +0.1% |
| 72 | +0.1% |
| 73 | +0.0% |
| 74 | -0.2% |
| 75 | +0.4% |
| 76 | -0.3% |
| 77 | -0.1% |
| 78 | +0.0% |
| 79 | +0.1% |
| 80 | +0.0% |
| 81 | -0.1% |
| 82 | +0.1% |
| 83 | +0.3% |
| 84 | +0.0% |
| 85 | +0.0% |
| 86 | +0.4% |
| 87 | -0.6% |
| 88 | -0.6% |
| 89 | +0.0% |
| 90 | -0.1% |
| 91 | +0.1% |
| 92 | +0.0% |
| 93 | +0.1% |
| 94 | +0.0% |
| 95 | -0.3% |
| 96 | +0.9% |
| 97 | -0.6% |
| 98 | +0.4% |
| 99 | +0.6% |
| 100 | +1.3% |
RM Difficulty Index
Race-Day Weather History
Race-morning conditions on this date over the past 10 years: median 63°F with a 57°F dew point and 6 mph wind. 6 of 10 years were warm enough to slow race pace.
| Year | Temp | Dew Pt | Wind | Rain | Sky |
|---|---|---|---|---|---|
| 2025 | 66°F | 58°F | 3 mph | — | Clear |
| 2024 | 55°F | 45°F | 3 mph | — | Partly cloudy |
| 2023 | 68°F | 60°F | 6 mph | — | Clear |
| 2022 | 52°F | 47°F | 5 mph | — | Clear |
| 2021 | 67°F | 65°F | 3 mph | — | Drizzle |
| 2020 | 49°F | 37°F | 7 mph | — | Partly cloudy |
| 2019 | 59°F | 55°F | 13 mph | — | Drizzle |
| 2018 | 72°F | 67°F | 12 mph | — | Partly cloudy |
| 2017 | 71°F | 65°F | 14 mph | — | Drizzle |
| 2016 | 60°F | 55°F | 2 mph | — | Partly cloudy |
Morning conditions (race window) on the Hennepin Hundred calendar date each year, from the ERA5 reanalysis archive — the race’s usual slot, not necessarily each edition’s exact day.
Hennepin Hundred Pace Calculator & Race Plan
The Hennepin Hundred is a 100-mile ultra on the flat I&M Canal Trail in Illinois. Despite being flat, 100 miles of running accumulates 883 meters of gain from the gentle trail undulations. The real challenge is managing fatigue, nutrition, and sleep deprivation over 20+ hours.
Our ultra-distance fatigue model is especially relevant here. The pace drift from mile 1 to mile 100 is massive, and having realistic splits helps you manage your effort and crew logistics.
Hennepin Hundred FAQ
When is the next Hennepin Hundred?›
The most recent Hennepin Hundred ran on Saturday, October 3, 2026. The next edition's date hasn't been announced yet.
How long is the Hennepin Hundred?›
The Hennepin Hundred is 100.0 miles (160.934 km). It runs in I&M Canal Trail, IL.
How much elevation gain does the Hennepin Hundred have?›
The Hennepin Hundred has about 2,897 ft (883 m) of climbing and 2,881 ft of descent, with a maximum grade of 11.7%.
Is the Hennepin Hundred flat, downhill, or hilly?›
The Hennepin Hundred starts and finishes at roughly the same elevation (net +5 m). With 2,897 ft of total climbing along the way, the profile rolls even though the net change is small.
How hard is the Hennepin Hundred?›
Runner's Math scores the Hennepin Hundred 36/100 (Moderate) — #1 of 1 ultra courses in our library, ranked by modeled time cost. The profile costs about 3:09 versus a flat course for a runner at 4:00-marathon pace.
What's the weather usually like at the Hennepin Hundred?›
Over the past 10 years on this date, median race-morning conditions were 63°F with a 57°F dew point and 6 mph wind. 6 of 10 years were warm enough to slow race pace.