Weather: Johannesburg Marathon

Historical weather data for race day in May. Use this to plan your race strategy, clothing, and hydration.

Racing conditions: Warm

18°C

Temperature

Range: 10°C – 25°C

45%

Humidity

Low — comfortable

15%

Rain Chance

Low chance of rain

May

Typical race month

Usually on a Sunday

Conditions

August falls in South Africa's late winter/early spring with cool, dry mornings and mild daytime temperatures. Runners benefit from low humidity and minimal rainfall, though the high altitude (1600m+) may affect breathing for those unaccustomed to elevation.

What to Wear

Singlet or short sleeve

Ideal racing temperatures

Hydration Strategy

Before the Race

Normal hydration. Drink to thirst in the 24 hours before. Avoid over-hydrating.

During the Race

Drink at aid stations every 3-4km. Alternate water and sports drink.

After the Race

Rehydrate within 30 minutes of finishing. A drink with electrolytes and some protein helps recovery.

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