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Big Rock, IL Weather & Growing Conditions

Overnight
64°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Some of the storms could produce heavy rain. Cloudy, with a low around 64. East southeast wind around 10 mph. Chance of precipitation is 70%. New rainfall amounts between a half and three quarters of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Overnight 64°F Showers And Thunderstorms Likely 10 mph ESE 74%
Saturday 79°F Showers And Thunderstorms then Showers And Thunderstorms Likely 5 to 10 mph ESE 98%
Saturday Night 64°F Showers And Thunderstorms 5 to 10 mph E 96%
Sunday 70°F Showers And Thunderstorms Likely 10 to 15 mph NNE 61%
Sunday Night 56°F Chance Rain Showers 15 mph NE 35%
Monday 65°F Chance Rain Showers 15 mph ENE 41%
Monday Night 51°F Chance Rain Showers then Mostly Cloudy 10 to 15 mph NE 25%
Tuesday 63°F Slight Chance Rain Showers 15 mph NE 18%
Tuesday Night 50°F Partly Cloudy 10 to 15 mph NE 9%
Wednesday 66°F Mostly Sunny 10 to 15 mph NE 6%
Wednesday Night 51°F Partly Cloudy 5 to 10 mph NNE 1%
Thursday 68°F Partly Sunny 5 to 10 mph NNE 2%
Thursday Night 52°F Partly Cloudy 5 to 10 mph NNE 2%
Friday 72°F Mostly Sunny 5 to 10 mph NE 3%

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

Growing snapshot for Big Rock, IL

Last spring frost
Apr 28
First fall frost
Oct 13
Growing season
166 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Chicago Aurora Muni Ap, Il (3.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.