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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.

Today
87°F
Mostly Cloudy
Mostly cloudy, with a high near 87. East southeast wind around 7 mph. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Delavan

WhenTempForecastWindPrecip
Today 87°F Mostly Cloudy 7 mph ESE 14%
Tonight 68°F Chance Showers And Thunderstorms 2 to 6 mph SSW 47%
Sunday 78°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 3 to 12 mph N 70%
Sunday Night 59°F Showers And Thunderstorms Likely then Chance Showers And Thunderstorms 12 to 15 mph NE 65%
Monday 67°F Showers And Thunderstorms Likely 14 mph NE 64%
Monday Night 54°F Chance Rain Showers 10 to 15 mph NE 46%
Tuesday 65°F Slight Chance Rain Showers 13 mph NE 23%
Tuesday Night 51°F Partly Cloudy 6 to 13 mph NNE 12%
Wednesday 68°F Mostly Sunny 9 mph NNE 3%
Wednesday Night 53°F Partly Cloudy 3 to 8 mph NNE 1%
Thursday 70°F Mostly Sunny 7 mph NNE 2%
Thursday Night 55°F Partly Cloudy 6 mph NE 2%
Friday 73°F Mostly Sunny 7 mph NE 3%
Friday Night 54°F Partly Cloudy 6 mph NE 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.