Harman US

Tonica, IL Weather & Growing Conditions

Overnight
57°F
Slight Chance Rain Showers
A slight chance of rain showers. Mostly cloudy. Low around 57, with temperatures rising to around 60 overnight. South southwest wind around 15 mph, with gusts as high as 25 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Overnight 57°F Slight Chance Rain Showers 15 mph SSW 17%
Wednesday 61°F Patchy Drizzle 15 mph SW 15%
Wednesday Night 47°F Patchy Drizzle then Mostly Cloudy 15 mph SW 10%
Thursday 58°F Mostly Cloudy then Chance Rain Showers 10 to 15 mph W 27%
Thursday Night 43°F Chance Rain Showers 10 mph NW 41%
Friday 51°F Partly Sunny 10 mph NNW 7%
Friday Night 33°F Partly Cloudy 0 to 10 mph NNW 0%
Saturday 52°F Sunny 0 to 5 mph NW 0%
Saturday Night 34°F Mostly Clear 0 to 5 mph W 1%
Sunday 57°F Sunny 5 to 10 mph W 3%
Sunday Night 35°F Clear 0 to 5 mph W 0%
Monday 62°F Sunny 0 to 10 mph SW 0%
Monday Night 40°F Mostly Clear 5 mph WSW 1%
Tuesday 63°F Sunny 5 mph WNW 1%

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

Growing snapshot for Tonica, IL

Last spring frost
Apr 24
First fall frost
Oct 18
Growing season
176 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Peru, Il (10.3 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.