Weather: Chicago Half Marathon
Historical weather data for race day in September. Use this to plan your race strategy, clothing, and hydration.
🌡️
21°C
Temperature
Range: 17°C – 25°C
💧
65%
Humidity
Moderate
🌧️
25%
Rain Chance
Low chance of rain
📅
September
Typical race month
Usually on a Sunday
📝 Conditions
Early fall weather in Chicago tends to be mild and pleasant, with comfortable temperatures and relatively low humidity. Occasional rain is possible, but September typically offers ideal running conditions.
👟 What to Wear
Light cap or visor
Shield from sun and heat
Sunscreen SPF 30+
21°C means sun exposure risk
Extra hydration plan
Increase fluid intake in heat
💧 Hydration Strategy
Before the Race
Hydrate aggressively in the 24 hours before. Aim for clear urine the morning of the race.
During the Race
Take water at every aid station. Consider sports drink for electrolytes. Don't wait until you're thirsty.
After the Race
Rehydrate within 30 minutes of finishing. A drink with electrolytes and some protein helps recovery.
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