Mammoth Bar Half Marathon 2027
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 3 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 - Mammoth Bar Half Marathon · 2027
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 | Castle Rock Aidkm 3.1 | FDL Aidkm 8.0 | Castle Rock Aidkm 18.1 |
|---|---|---|---|
| Water | ✕ | ✕ | ✕ |
| Brand products | ✕ | ✕ | ✕ |
Elevation profile
The course and its aid stations
Mammoth Bar Half Marathon: 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 3h30 to 2h19, and the aid-station stop budget from 0h04 to 0h02. The longer the race, the more stops weigh: this is time you should plan to spend standing still, not only running.
Below a UTMB® Index of roughly 505, the overall cut-off of 3h30 is no longer reachable at the estimated pace.
| UTMB® Index | Estimated time | Of which stops | Night hours | Carbs | Fluid | Sodium | Cut-off margin |
|---|---|---|---|---|---|---|---|
| 500 | 3h30 | 0h04 | — | 210 g | 2.5 L | 1,752 mg | +0h00 |
| 550 | 3h09 | 0h04 | — | 189 g | 2.2 L | 1,573 mg | +0h21 |
| 600 | 2h55 | 0h03 | — | 175 g | 2 L | 1,459 mg | +0h35 |
| 650 | 2h44 | 0h03 | — | 164 g | 1.9 L | 1,370 mg | +0h46 |
| 700 | 2h35 | 0h02 | — | 155 g | 1.8 L | 1,296 mg | +0h55 |
| 750 | 2h28 | 0h02 | — | 148 g | 1.7 L | 1,233 mg | +1h02 |
| 800 | 2h19 | 0h02 | — | 139 g | 1.6 L | 1,160 mg | +1h11 |
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
- Pumpkin Hollar 25K25 km · 300 m D+ · October 17, 2026
- Fort Collins - Half Marathon22 km · 460 m D+ · October 18, 2026
- Javelina Jackass 31k31 km · 322 m D+ · October 31, 2026
- Coldwater Trail 25k25 km · 619 m D+ · November 1, 2026
- HOKA Pacific Trails California by UTMB - 25K®25 km · 667 m D+ · November 15, 2026
- Lost Lake 25K25 km · 954 m D+ · March 6, 2027
- Desert RATS Trail Running Festival - 21K21 km · 642 m D+ · April 11, 2027
- The Canyons Endurance Runs - 25K25 km · 810 m D+ · April 23, 2027
- Rothrock - 25K27 km · 1,065 m D+ · May 16, 2027
Sources and method
- Time projection — les temps par cote sont repris des passages réels des coureurs de chaque tranche sur les éditions précédentes de cette course, arrêts aux ravitaillements compris. Aucune formule n'intervient tant que ces résultats existent.
- 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 — Mammoth Bar Half Marathon
Weather for Mammoth Bar Half Marathon
The weather for Mammoth Bar Half Marathon 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 Mammoth Bar Half Marathon, hour by hour on the courseFrequently asked questions
How many checkpoints?
Mammoth Bar Half Marathon has 4 checkpoints: 3 aid stations and 1 checkpoint with undocumented contents. Details are in the two tables above.
What's the longest segment without aid?
The one leading to Castle Rock Aid: 10.2 km and 741 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?
Mammoth Bar Half Marathon is 21 km long with 1438 m of elevation gain.
How long to finish?
With a UTMB Index of 600 (average runner), the estimated time is around 2h55 for Mammoth Bar Half Marathon.
What's the weather forecast?
The weather for Mammoth Bar Half Marathon 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 Mammoth Bar Half Marathon?
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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