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Delavan, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Delavan, a city in Tazewell County, Illinois.

Overnight
69°F
Partly Cloudy
Partly cloudy, with a low around 69. Southeast wind around 8 mph, with gusts as high as 17 mph.

7-day forecast for Delavan

WhenTempForecastWindPrecip
Overnight 69°F Partly Cloudy 8 mph SE 14%
Saturday 89°F Slight Chance Showers And Thunderstorms then Mostly Cloudy 8 mph S 18%
Saturday Night 68°F Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms 7 mph SE 43%
Sunday 80°F Showers And Thunderstorms Likely 3 to 12 mph NNE 63%
Sunday Night 60°F Showers And Thunderstorms Likely 10 to 14 mph NE 64%
Monday 68°F Showers And Thunderstorms Likely 14 mph ENE 64%
Monday Night 55°F Chance Showers And Thunderstorms 10 to 15 mph NE 47%
Tuesday 66°F Chance Rain Showers then Mostly Cloudy 13 mph NE 25%
Tuesday Night 51°F Mostly Cloudy 6 to 12 mph NNE 5%
Wednesday 69°F Mostly Sunny 9 mph NNE 4%
Wednesday Night 53°F Partly Cloudy 3 to 8 mph NNE 1%
Thursday 70°F Mostly Sunny 3 to 7 mph NNE 2%
Thursday Night 55°F Partly Cloudy 2 to 6 mph NE 3%
Friday 73°F Mostly Sunny 3 to 7 mph NNE 3%

Forecast source: National Weather Service (api.weather.gov) for Delavan (40.371, -89.546). Updated through the day.

Growing snapshot for Delavan

Last spring frost
Apr 17
First fall frost
Oct 18
Growing season
182 days
Hardiness zone
6a

More local growing data for Delavan: nearby ZIP 61734 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, Mason City 4Se, Il (16.1 mi from Delavan). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.