Dupo, IL Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Dupo, a village in St. Clair County, Illinois.
Overnight
65°F
Clear
Clear, with a low around 65. East wind around 1 mph.
7-day forecast for Dupo
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 65°F | Clear | 1 mph E | 0% |
| Tuesday | 89°F | Sunny | 3 mph SE | 0% |
| Tuesday Night | 68°F | Mostly Clear | 5 mph SE | 0% |
| Wednesday | 91°F | Sunny | 2 to 6 mph S | 7% |
| Wednesday Night | 72°F | Slight Chance Showers And Thunderstorms | 7 mph S | 61% |
| Thursday | 88°F | Showers And Thunderstorms Likely | 6 mph S | 68% |
| Thursday Night | 71°F | Chance Showers And Thunderstorms | 3 mph S | 39% |
| Friday | 88°F | Chance Showers And Thunderstorms | 3 mph SW | 39% |
| Friday Night | 70°F | Chance Showers And Thunderstorms | 3 mph S | 31% |
| Saturday | 90°F | Chance Showers And Thunderstorms then Mostly Sunny | 5 mph S | 31% |
| Saturday Night | 72°F | Mostly Clear | 6 mph S | 7% |
| Sunday | 92°F | Sunny | 7 mph S | 7% |
| Sunday Night | 74°F | Mostly Clear | 7 mph S | 5% |
| Monday | 94°F | Sunny | 8 mph SW | 5% |
Forecast source: National Weather Service (api.weather.gov) for Dupo (38.516, -90.218). Updated through the day.
Growing snapshot for Dupo
Last spring frost
Apr 6
First fall frost
Oct 27
Growing season
203 days
Hardiness zone
7a
More local growing data for Dupo: nearby ZIP 62240 weather · frost dates · planting calendar · Illinois frost dates
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Climate data from the nearest NOAA station, Cahokia, Il (4.6 mi from Dupo). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.