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Darmstadt, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Darmstadt, a community in St. Clair County, Illinois.

This Afternoon
97°F
Mostly Sunny
Mostly sunny, with a high near 97. Heat index values as high as 102. West wind 3 to 7 mph.

7-day forecast for Darmstadt

WhenTempForecastWindPrecip
This Afternoon 97°F Mostly Sunny 3 to 7 mph W 10%
Tonight 72°F Partly Cloudy 3 mph S 2%
Sunday 94°F Mostly Sunny 2 to 6 mph W 4%
Sunday Night 66°F Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 3 to 7 mph NE 59%
Monday 82°F Showers And Thunderstorms Likely 3 to 8 mph NE 57%
Monday Night 59°F Chance Showers And Thunderstorms 3 to 8 mph NE 47%
Tuesday 73°F Chance Showers And Thunderstorms then Partly Sunny 6 to 12 mph N 39%
Tuesday Night 54°F Mostly Cloudy 3 to 10 mph N 1%
Wednesday 74°F Mostly Sunny 6 to 9 mph N 0%
Wednesday Night 53°F Partly Cloudy 2 to 7 mph N 0%
Thursday 76°F Mostly Sunny 2 to 6 mph N 1%
Thursday Night 57°F Mostly Cloudy 1 to 5 mph N 4%
Friday 79°F Slight Chance Rain Showers 1 to 6 mph NE 15%
Friday Night 56°F Slight Chance Rain Showers then Partly Cloudy 5 mph NE 15%

Forecast source: National Weather Service (api.weather.gov) for Darmstadt (38.319, -89.729). Updated through the day.

Growing snapshot for Darmstadt

Last spring frost
Apr 12
First fall frost
Oct 22
Growing season
191 days
Hardiness zone
7a

More local growing data for Darmstadt: nearby ZIP 62257 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, Sparta 1 W, Il (11.6 mi from Darmstadt). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.