Weather World
Piatt County, IL Official SitePiatt County, IL 7-Day Night Weather Forecast
Quick Weather Clicks
Settings
Sun & Moon
Weather Quote O' the Day
Piatt County, IL Weather Forecast
Piatt County, IL Weather Forecast Date: 620 PM CDT Fri Oct 16 2026
The area/counties/county of: Piatt, including the city of Monticello.or toggle through each period.
Tonight... Mostly cloudy with a chance of showers this evening, then mostly clear after midnight. Cooler with lows in the mid 30s. North winds 15 to 20 mph. Chance of rain 30%.
Saturday... Patchy frost in the morning. Sunny. Highs in the upper 50s. North winds 5 to 10 mph.
Saturday Night... Clear. Areas of frost after midnight. Lows in the lower 30s. Southeast winds around 5 mph.
Sunday... Widespread frost in the morning. Sunny. Highs in the mid 60s. South winds 5 to 10 mph.
Sunday Night... Clear. Lows in the mid 30s. Southeast winds around 5 mph.
Monday... Mostly clear. Highs in the mid 70s. Lows in the lower 40s.
Tuesday... Mostly clear. Highs in the mid 70s. Lows in the lower 40s.
Wednesday... Mostly clear. Highs in the mid 70s. Lows in the lower 40s.
Thursday... Mostly clear. Highs in the mid 70s. Lows in the lower 40s.
Thursday Night... Mostly clear. Lows in the upper 40s. Highs in the upper 70s.
POP = Probability of Precipitation
Piatt County Radar Loop
Use the map search tool if you want to place a location marker on the radar map...