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Keithsburg, IL Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Keithsburg, a city in Mercer County, Illinois.

Overnight
69°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms between 2am and 4am, then patchy fog and a slight chance of showers and thunderstorms. Partly cloudy, with a low around 69. Southeast wind around 5 mph. Chance of precipitation is 20%.

7-day forecast for Keithsburg

WhenTempForecastWindPrecip
Overnight 69°F Slight Chance Showers And Thunderstorms 5 mph SE 23%
Saturday 85°F Patchy Fog 5 to 10 mph S 46%
Saturday Night 66°F Chance Showers And Thunderstorms then Showers And Thunderstorms 5 mph W 80%
Sunday 73°F Showers And Thunderstorms 5 to 15 mph NE 80%
Sunday Night 58°F Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 10 to 15 mph NE 58%
Monday 65°F Showers And Thunderstorms Likely 10 to 15 mph NE 63%
Monday Night 53°F Chance Rain Showers 10 mph NE 52%
Tuesday 64°F Chance Rain Showers 10 mph NE 39%
Tuesday Night 49°F Mostly Clear 5 to 10 mph NE 5%
Wednesday 68°F Mostly Sunny 5 mph NE 1%
Wednesday Night 52°F Partly Cloudy 0 to 5 mph NE 1%
Thursday 70°F Partly Sunny 0 to 5 mph NE 5%
Thursday Night 54°F Partly Cloudy 0 to 5 mph NE 4%
Friday 73°F Mostly Sunny 0 to 5 mph NE 4%

Forecast source: National Weather Service (api.weather.gov) for Keithsburg (41.100, -90.936). Updated through the day.

Growing snapshot for Keithsburg

Last spring frost
Apr 14
First fall frost
Oct 24
Growing season
190 days
Hardiness zone
5b

More local growing data for Keithsburg: nearby ZIP 61442 weather · frost dates · planting calendar · Illinois frost dates

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Climate data from the nearest NOAA station, New Boston Dam 17, Il (9.3 mi from Keithsburg). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.