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Pecatonica, IL Weather & Growing Conditions

Tonight
61°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely after 11pm. Some of the storms could produce heavy rain. Mostly cloudy, with a low around 61. East southeast wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 70%. New rainfall amounts between three quarters and one inch possible.

7-day forecast

WhenTempForecastWindPrecip
Tonight 61°F Showers And Thunderstorms Likely 10 to 15 mph ESE 73%
Saturday 77°F Showers And Thunderstorms then Showers And Thunderstorms Likely 5 to 10 mph SE 93%
Saturday Night 61°F Showers And Thunderstorms Likely 5 to 10 mph NE 74%
Sunday 66°F Showers And Thunderstorms Likely 10 to 20 mph NE 66%
Sunday Night 52°F Chance Rain Showers 15 mph ENE 46%
Monday 64°F Chance Rain Showers 15 to 20 mph ENE 42%
Monday Night 48°F Chance Rain Showers 10 to 15 mph NE 42%
Tuesday 62°F Chance Rain Showers 10 to 15 mph NE 31%
Tuesday Night 46°F Mostly Cloudy 5 to 15 mph NE 9%
Wednesday 66°F Mostly Sunny 5 to 10 mph NE 4%
Wednesday Night 47°F Partly Cloudy 5 to 10 mph NE 2%
Thursday 67°F Mostly Sunny 5 mph NNE 5%
Thursday Night 49°F Partly Cloudy 0 to 5 mph NE 5%
Friday 70°F Mostly Sunny 0 to 5 mph NE 5%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Pecatonica, IL

Last spring frost
Apr 26
First fall frost
Oct 13
Growing season
169 days
Hardiness zone
5b

Explore more for Pecatonica, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Freeport Waste Wtp, Il (13.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.