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Thayer, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Thayer, a village in Sangamon County, Illinois.

Tonight
72°F
Slight Chance Showers And Thunderstorms then Partly Cloudy
A slight chance of showers and thunderstorms before 8pm. Partly cloudy, with a low around 72. East southeast wind around 8 mph. Chance of precipitation is 20%.

7-day forecast for Thayer

WhenTempForecastWindPrecip
Tonight 72°F Slight Chance Showers And Thunderstorms then Partly Cloudy 8 mph ESE 15%
Saturday 94°F Partly Sunny 9 mph SSW 7%
Saturday Night 70°F Mostly Cloudy then Slight Chance Rain Showers 5 to 8 mph SSW 20%
Sunday 88°F Chance Rain Showers 2 to 7 mph NW 43%
Sunday Night 62°F Chance Showers And Thunderstorms 9 mph NNE 65%
Monday 74°F Showers And Thunderstorms Likely 8 to 12 mph NE 65%
Monday Night 56°F Chance Showers And Thunderstorms 8 to 12 mph NE 47%
Tuesday 70°F Chance Rain Showers then Mostly Cloudy 12 mph NNE 29%
Tuesday Night 51°F Mostly Cloudy 5 to 10 mph NNE 4%
Wednesday 73°F Partly Sunny 6 to 9 mph NNE 1%
Wednesday Night 53°F Partly Cloudy 2 to 7 mph NNE 1%
Thursday 73°F Mostly Sunny 3 to 7 mph NNE 3%
Thursday Night 55°F Partly Cloudy 2 to 6 mph NNE 4%
Friday 75°F Mostly Sunny 3 to 7 mph NNE 4%

Forecast source: National Weather Service (api.weather.gov) for Thayer (39.540, -89.758). Updated through the day.

Growing snapshot for Thayer

Last spring frost
Apr 7
First fall frost
Oct 29
Growing season
205 days
Hardiness zone
6a

More local growing data for Thayer: nearby ZIP 62689 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, Virden, Il (1.9 mi from Thayer). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.