Beaverhead Marathon Full & Half

Beaverhead Marathon Full & Half is a Marathon (26.2 mi) marathon held in Dillon, MT, US. Based on 5 years of historical weather data, athletes can expect median race-day temperatures around 85°F.

Temperatures at Beaverhead Marathon Full & Half typically range from 77°F to 91°F. This puts the race squarely in high heat risk territory. Sweat rates can increase 15–25% in these conditions, meaning both fluid and sodium demands rise significantly. Athletes should plan for increased hydration, consider pre-cooling strategies, and expect pace adjustments — even well-trained runners slow 1–3% per 10°F above 60°F. Humidity is also a factor here, with levels reaching 77% on warmer days. High humidity impairs sweat evaporation — your body's primary cooling mechanism — so perceived effort rises even when temperatures look manageable on paper.

Marathon fueling is about precision. Current sports science supports 60–90g of carbohydrates per hour for events over 2.5 hours, with experienced athletes pushing up to 120g/hr using glucose-fructose combinations. Start conservative in the first hour (around 70% of target) and build to full intake by hour two. Given the heat potential at this race, sodium intake of 600–1000mg per hour becomes critical to offset sweat losses.