The Naturalist 2026
The forecast arrives five days before the start.
Here you'll find the elevation profile, an estimated finish time based on your UTMB Index and details of the 5 aid stations to plan your nutrition and hydration segment by segment.
What's your time based on your UTMB?
Times estimated by the RAVIT model, learned from real ultra-trail finish times. Enter your UTMB Index (utmb.world) to get a personalized estimate.
Cut-off times and crew - The Naturalist · 2026
Data from the official race rules, checked for every edition. The race rules prevail. Positions are interpolated along the GPX track and are a guide, not official course marking.
What you'll find at each aid station
| Product | Wallace Branchkm 5.6 | Harrison Gapkm 14.5 | Wayah Bald Summitkm 23.3 | Harrison Gapkm 31.4 | Wallace Branchkm 40.2 |
|---|---|---|---|---|---|
| Water | available | available | available | available | available |
| Brand products | unavailable | available | available | available | unavailable |
Elevation profile
The course and its aid stations
The Naturalist: times, aid-station stops and fuelling needs by UTMB® Index
Between a UTMB® Index of 500 and 800, the estimated finish time on this race runs from 6h28 to 4h04, and the aid-station stop budget from 0h14 to 0h05. The longer the race, the more stops weigh: this is time you should plan to spend standing still, not only running.
Source
| UTMB® Index | Estimated time | Of which stops | Night hours | Carbs | Fluid | Sodium |
|---|---|---|---|---|---|---|
| 500 | 6h28 | 0h14 | — | 388 g | 4.5 L | 3,230 mg |
| 550 | 5h53 | 0h11 | — | 353 g | 4.1 L | 2,938 mg |
| 600 | 5h21 | 0h09 | — | 321 g | 3.7 L | 2,674 mg |
| 650 | 4h58 | 0h08 | — | 298 g | 3.5 L | 2,486 mg |
| 700 | 4h39 | 0h07 | — | 279 g | 3.3 L | 2,324 mg |
| 750 | 4h23 | 0h06 | — | 263 g | 3.1 L | 2,188 mg |
| 800 | 4h04 | 0h05 | — | 244 g | 2.8 L | 2,032 mg |
Figures based on 60 g of carbohydrate, 700 mL of fluid and 500 mg of sodium per hour, "average" preparation and mild conditions (15–25 °C). Above 25 °C, count on roughly 900 mL/h and 700 mg/h. Carbohydrate intake is trained: 60 g/h is a floor, 90 g/h assumes a glucose-fructose blend and a gut used to it.
Other trails worth preparing for
- Fort Collins - Marathon43 km · 1,162 m D+ · October 18, 2026
- Bridge Burner 35mile58 km · 1,616 m D+ · October 24, 2026
- Javelina Jackass 31k31 km · 322 m D+ · October 31, 2026
- Coldwater 50k52 km · 1,293 m D+ · November 1, 2026
- Lake Chabot 50K49 km · 1,896 m D+ · November 7, 2026
- Mt. Tam 50k48 km · 2,005 m D+ · November 7, 2026
- Red Rock Canyon 50k49 km · 988 m D+ · November 14, 2026
- HOKA Pacific Trails California by UTMB - 50K®52 km · 1,548 m D+ · November 14, 2026
- VHTRC Redeye 50K50 km · 1,027 m D+ · December 30, 2026
Sources and method
- Time projection — times by UTMB Index are taken from the actual splits of runners in each level band on previous editions of this race, aid station stops included. No formula is used as long as these results exist.
- Trail nutrition — hourly targets for carbohydrate, fluid and sodium follow the commonly accepted ultra-endurance guidance. La Clinique du Coureur — Fuelling in trail running
- Course, aid stations and cut-offs — taken from the event's official rules, which prevail in case of any discrepancy. Official site — The Naturalist
Weather for The Naturalist
The weather for The Naturalist will appear here as soon as the forecast models reach that date, around five days before the start: feels-like temperature, rain, snow, wind and storms, section by section and at your passage time.
Detailed weather for The Naturalist, hour by hour on the courseFrequently asked questions
How many checkpoints?
The Naturalist has 6 checkpoints: 3 aid stations, 2 water points, and 1 checkpoint with undocumented contents. Details are in the two tables above.
What's the longest segment without aid?
The one leading to Wayah Bald Summit: 8.9 km and 726 m elevation gain. That's the one to load up for first.
How do I find the exact location of an aid station?
The Google Maps icon in the “Access” column opens the aid station's location: handy for planning your crew's routes.
What distance and elevation gain?
The Naturalist is 46 km long with 1920 m of elevation gain.
How long to finish?
With a UTMB Index of 600 (average runner), the estimated time is around 5h21 for The Naturalist.
What's the weather forecast?
The weather for The Naturalist will be published on this page around five days before the start, once the forecast models reach the race date. It will be detailed section by section: feels-like temperature, rain, snow, wind and storms.
Want to stack the odds in your favor for The Naturalist?
In 2 minutes, RAVIT generates your complete plan: segment-by-segment time, carbs, water and sodium at every aid station, printable roadbook.
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