Weather in Harristown, IL
Updated 2026-09-26 11:00 local time · ZIP codes 62537
Overcast
No government weather alerts were returned for this location at the latest update.
Next hours
66°12% rain68°10% rain70°9% rain
71°6% rain71°9% rain71°10% rain70°9% rain70°10% rain
68°11% rain67°12% rain65°12% rain65°12% rain3-day weather forecast
Weather details
Sunrise, sunset and moon
Key weather changes ahead
Weather insights for today
Rain chance stays relatively low over the next 12 hours (up to 12%).
It feels like 62°F with winds near 7 mph.
71°F, 6% rain chance and 4 mph wind.
Visibility is around 6 mi; gusts may reach 17 mph.
Current temperature is 66°F, wind 7 mph, rain chance up to 12%.
UV index is 4. Sunscreen and sunglasses are sensible for longer outdoor time.
Local weather characteristics in Harristown
Illinois has four distinct seasons with hot, humid summers, cold winters, strong frontal changes and frequent spring and summer thunderstorms.
Harristown is part of the Midwest weather region. The forecast point is near 39.85°N latitude and 89.08°W longitude. Local temperature, wind and precipitation can still differ from nearby places, especially where terrain, coastlines or urban development create small-scale weather changes.
Harristown weather today
Overcast and 66°F in Harristown, IL. Today's high is 71°F with a 10% rain chance. Winds are around 7 mph with gusts near 8 mph. Relative humidity is 49%, pressure is 30.16 inHg, and visibility is about 6 miles.
Tonight and tomorrow in Harristown
Sunrise is at 06:47 AM and sunset is at 06:47 PM. Tomorrow's forecast calls for Overcast with a high near 75°F and a low near 58°F. The maximum rain chance is 6%.