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Rio, IL Weather & Growing Conditions

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

This Afternoon
77°F
Mostly Sunny
Mostly sunny, with a high near 77. East southeast wind around 10 mph, with gusts as high as 17 mph. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Rio

WhenTempForecastWindPrecip
This Afternoon 77°F Mostly Sunny 10 mph ESE 2%
Tonight 68°F Partly Cloudy then Chance Showers And Thunderstorms 8 to 12 mph ESE 44%
Saturday 84°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 10 mph SSE 55%
Saturday Night 65°F Chance Showers And Thunderstorms then Showers And Thunderstorms 8 mph N 76%
Sunday 73°F Showers And Thunderstorms Likely 7 to 15 mph NE 74%
Sunday Night 57°F Showers And Thunderstorms Likely 16 mph NE 66%
Monday 64°F Showers And Thunderstorms Likely 17 mph ENE 63%
Monday Night 53°F Chance Rain Showers 13 to 16 mph NE 48%
Tuesday 63°F Chance Rain Showers 15 mph NE 36%
Tuesday Night 49°F Mostly Cloudy 5 to 12 mph NNE 5%
Wednesday 67°F Mostly Sunny 9 mph NNE 2%
Wednesday Night 52°F Partly Cloudy 2 to 6 mph NE 2%
Thursday 68°F Mostly Sunny 6 mph NNE 4%
Thursday Night 54°F Partly Cloudy 5 mph NE 5%

Forecast source: National Weather Service (api.weather.gov) for Rio (41.109, -90.399). Updated through the day.

Growing snapshot for Rio

Last spring frost
Apr 20
First fall frost
Oct 19
Growing season
180 days
Hardiness zone
5b

More local growing data for Rio: nearby ZIP 61472 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, Galesburg, Il (10.8 mi from Rio). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.