Delavan, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Delavan, a city in Tazewell County, Illinois.
Tonight
54°F
Rain
Rain before 4am, then a slight chance of rain showers. Mostly cloudy, with a low around 54. South southwest wind 12 to 15 mph, with gusts as high as 23 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.
7-day forecast for Delavan
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 54°F | Rain | 12 to 15 mph SSW | 81% |
| Wednesday | 60°F | Mostly Cloudy | 15 mph SW | 14% |
| Wednesday Night | 45°F | Mostly Cloudy | 12 mph SW | 2% |
| Thursday | 60°F | Mostly Sunny | 9 to 14 mph WSW | 7% |
| Thursday Night | 43°F | Mostly Cloudy then Slight Chance Light Rain | 5 to 8 mph NW | 24% |
| Friday | 55°F | Mostly Cloudy then Slight Chance Light Rain | 7 to 10 mph NNW | 16% |
| Friday Night | 36°F | Partly Cloudy | 2 to 8 mph NNW | 4% |
| Saturday | 54°F | Mostly Sunny | 5 mph WNW | 2% |
| Saturday Night | 34°F | Partly Cloudy | 2 mph W | 2% |
| Sunday | 60°F | Sunny | 2 to 9 mph WNW | 12% |
| Sunday Night | 35°F | Mostly Clear | 6 mph W | 5% |
| Monday | 65°F | Sunny | 3 to 10 mph SW | 2% |
| Monday Night | 40°F | Mostly Clear | 3 to 7 mph WSW | 1% |
| Tuesday | 67°F | Sunny | 3 to 7 mph W | 1% |
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
Nearby towns & communities
Armington
Creve Coeur
Deer Creek
East Peoria
Green Valley
Heritage Lake
Hopedale
Mackinaw
Manito
Marquette Heights
Minier
Morton
North Pekin
Pekin
South Pekin
Tremont
Washington
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 Nov 4, 2026.