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Niantic, IL Weather & Growing Conditions

Today
90°F
Mostly Cloudy
Mostly cloudy, with a high near 90. South southwest wind around 7 mph.

7-day forecast

WhenTempForecastWindPrecip
Today 90°F Mostly Cloudy 7 mph SSW 14%
Tonight 69°F Partly Cloudy then Slight Chance Showers And Thunderstorms 6 mph SSW 21%
Sunday 83°F Chance Showers And Thunderstorms 3 to 12 mph N 48%
Sunday Night 60°F Chance Showers And Thunderstorms 14 mph NE 63%
Monday 70°F Showers And Thunderstorms Likely 16 mph NE 70%
Monday Night 54°F Chance Rain Showers 12 to 15 mph NE 49%
Tuesday 67°F Slight Chance Rain Showers 16 mph NE 20%
Tuesday Night 52°F Slight Chance Rain Showers then Mostly Cloudy 7 to 14 mph NNE 17%
Wednesday 70°F Mostly Sunny 12 mph NNE 3%
Wednesday Night 53°F Partly Cloudy 5 to 10 mph NNE 2%
Thursday 72°F Mostly Sunny 6 to 10 mph NNE 2%
Thursday Night 55°F Partly Cloudy 5 to 9 mph NNE 2%
Friday 75°F Mostly Sunny 5 to 10 mph NE 2%
Friday Night 54°F Partly Cloudy 5 to 9 mph NE 2%

Forecast source: National Weather Service (api.weather.gov). Updated through the day.

Growing snapshot for Niantic, IL

Last spring frost
Apr 14
First fall frost
Oct 24
Growing season
192 days
Hardiness zone
6a

Explore more for Niantic, IL: full frost dates · planting calendar · Illinois frost dates

Climate data from the nearest NOAA station, Decatur Wtp, Il (11 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.