Races›Ultra 50K

Worlds End Ultramarathon

Race-specific weather data and nutrition strategy for Worlds End Ultramarathon in Forksville, PA, US.

RunningUltra 50K (31.1 mi)Registration Open
LocationForksville, PA, US
Date
May 30, 2026
Register on RunSignUpBuild Your Fueling PlanOfficial website
Race Location41.49°, -76.60°
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Race-Day Conditions

High Heat Risk
Temperature
71°F

57–86°F range

Humidity
71%

47–90% range

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

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High heat risk

Race-day temperatures can reach 86°F. Expect 15-25% higher sweat rates. Increase sodium to 800-1200 mg/hr and plan for more frequent fluid intake. Pre-cool with ice and cold fluids.

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High humidity conditions

Humidity averaging 71% combined with warm temperatures impairs sweat evaporation. Your body works harder to cool itself. Reduce intensity expectations and increase fluid intake.

Sample Ultra 50K Nutrition Plan

Based on a 155 lb runner finishing in ~6 hours. Your plan will differ based on body weight, experience, and conditions.

HourCarbsFluidSodiumExample
Hour 150g19oz400mg1 gel + sports drink
Hour 265g22oz500mg2 gels + water
Hour 365g22oz500mgChews + drink mix
Hour 460g22oz500mgGel + banana
Hour 555g19oz500mgPB sandwich + water
Hour 650g17oz400mgGel + sports drink
Total345g121oz2800mg

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

What to Expect at Worlds End Ultramarathon

Worlds End Ultramarathon is a Ultra 50K (31.1 mi) ultra 50k held in Forksville, PA, US. Based on 5 years of historical weather data, athletes can expect median race-day temperatures around 71°F.

Temperatures at Worlds End Ultramarathon typically range from 57°F to 86°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 90% 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.

Ultra-distance racing demands a flexible nutrition strategy. Gut absorption efficiency declines over many hours, so plan for variety — alternating between gels, chews, real food, and liquids helps prevent flavor fatigue and GI rebellion. Many ultra runners find that what works at hour 3 is intolerable by hour 10. Build your plan with options, not rigid prescriptions.

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 Ultra 50K.
What is the typical race-day weather?
Based on 5 years of historical data, race-day temperatures at Forksville, PA typically range from 57°F to 86°F (median 71°F). Humidity ranges from 47% to 90%.
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 Forksville, PA 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 Ultra 50K 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%