Races
Coldwater Rumble 100
Estrella Mountain Regional Park. Two red loops. Three blue loops. One hundred miles under a thousand feet of peak elevation but eight thousand feet of rollers.
101.3 mi+3,613 ft-3,613 ft30 hours926 ft to 1,384 fttech 5/10Checkpoints per race bookEstrella Mountainsloop formatJanuary hundredJanuary
Distance101.3 mi
Gain+3,613 ft
Loss-3,613 ft
Altitude926 ft to 1,384 ft
Technicality5/10
Air40°F to 75°F
- Start1,020 ft
- High1,384 ft
- Low926 ft
- Finish1,020 ft
Terrain
Geometryderived
Steepest drop249 ft-2.2% over 2.1 mi
Night miles51 misunset near 18:00 local
Weather at the cruxderived
At hour 9 of race, feels like 20 C (76 F).Sample of 7 race days, medium confidence.At hour 9 of race, apparent temperature P90 is 20 C / 67 F.
The cruxThree 27-mile blue loops after two 10-mile red loops in January heat (near mile 66)
Course DNA
The Course
Coldwater Rumble 100 runs 101.3 mi through Goodyear, Arizona. +3,613 ft gain and -3,613 ft loss. Surfaces skew 90% trail / 10% dirt road. Three 27-mile blue loops after two 10-mile red loops in January heat. High point near 1,384 ft. Low near 926 ft. January temps run 40°F to 75°F. The course rewards patience early and punishes rushed descents after mile 51.
The Work
Train for 3,613 feet of climbing across 101.3 mi. Back-to-back long runs on trail. Practice power-hiking grades above 15 percent. 30 hours total means limited margin: rehearse fueling every 45 to 60 minutes and downhill eccentric work weekly. Technicality 5/10. Build a block that simulates the crux near mile 66.
Kit
January in Goodyear, Arizona: plan for 40°F to 75°F. Mandatory shell if rain is in forecast. Headlamp with spare batteries if 30 hours pushes past dark. Poles help on sustained climbs above mile 25. Vest capacity for 2 liters minimum. Shoes matched to 90% trail: lugs for mud, rock plate if the course turns technical after mile 51.
Race Day
Hold effort through mile 25. The field often splits on the first big climb after mile 51. Three 27-mile blue loops after two 10-mile red loops in January heat near mile 66 is where time is won or lost. Walk the steep pinches. Run the flats and gentle downhills. Crew at major aids: socks, calories, ice if hot. Transitions under 5 minutes when possible. Final third is 33 miles of fatigue management. Finish with reserve for the last descent.
Results
Coldwater Rumble 100 finish lines.
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