Races›Marathon

Modesto Marathon

Race-specific weather data and nutrition strategy for Modesto Marathon in Modesto, CA, US.

RunningMarathon (26.2 mi)Registration Open
LocationModesto, CA, US
Date
April 4, 2027
Register on RunSignUpBuild Your Fueling PlanOfficial website
Race Location37.64°, -121.00°
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Race-Day Conditions

Moderate Heat Risk
Temperature
72°F

56–85°F range

Humidity
61%

44–76% range

5-year average via Open-Meteo. 80% of race days fall within the range shown. Updated Mar 30, 2026.

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Moderate heat risk

Temperatures may reach 85°F. Plan for 10-15% higher sweat rates than cool conditions. Ensure adequate sodium intake (600-900 mg/hr) and consider pre-cooling strategies.

Sample Marathon Nutrition Plan

Based on a 155 lb runner finishing in ~4 hours. Your plan will differ based on body weight, experience, and conditions.

HourCarbsFluidSodiumExample
Hour 150g18oz400mg1 gel + sports drink
Hour 270g20oz500mg2 gels + water
Hour 370g20oz500mg1 gel + 4 chews
Hour 450g15oz400mg1 gel + sports drink
Total240g73oz1800mg

These are general estimates. Get your personalized plan for this race →

What to Expect at Modesto Marathon

Modesto Marathon is a Marathon (26.2 mi) marathon held in Modesto, CA, US. Based on 5 years of historical weather data, athletes can expect median race-day temperatures around 72°F.

Temperatures at Modesto Marathon typically range from 56°F to 85°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 76% 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.

We do our best to keep race details accurate and up to date, but things can change and occasionally we simply get something wrong.

Always check the official website for the most complete and current information.

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Fueling and hydration suggestions are based on published sports science research including ACSM position stands, ISSN guidelines, and peer-reviewed work by Jeukendrup, Sawka, and others. This is not medical or dietary advice — individual needs vary. Always test your nutrition strategy in training before race day.

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Frequently Asked Questions

What should I eat during the race?
Your nutrition plan depends on your body weight, experience level, and race-day conditions. Use our free calculator to get a personalized, hour-by-hour fueling plan with specific carb, fluid, and sodium targets for this Marathon.
What is the typical race-day weather?
Based on 5 years of historical data, race-day temperatures at Modesto, CA typically range from 56°F to 85°F (median 72°F). Humidity ranges from 44% to 76%.
How much water should I drink?
Fluid needs vary based on your sweat rate, body weight, and race-day temperature. A typical range is 400-800 mL per hour, but hotter conditions at Modesto, CA may require more. Our calculator provides personalized fluid targets adjusted for the expected weather.
How many calories do I need?
Rather than replacing all calories burned, focus on carbohydrate intake — the primary fuel for endurance performance. Target 30-50% of caloric expenditure through carbs. Our calculator computes the exact hourly targets based on your Marathon pace and body weight.
When should I start fueling?
Begin fueling within the first 30-45 minutes. Start at about 70% of your target intake and ramp up to full by hour 2. This gives your gut time to adjust. Starting too late makes it nearly impossible to catch up on carbs and fluids.
Source: runsignup_apiView sourceVerified: Mar 30, 2026Confidence: 95%