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Knoxville, IA Weather & Growing Conditions

Overnight
70°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Mostly cloudy, with a low around 70. South southeast wind around 8 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Overnight 70°F Chance Showers And Thunderstorms 8 mph SSE 28%
Saturday 82°F Chance Showers And Thunderstorms 10 mph SW 50%
Saturday Night 63°F Showers And Thunderstorms Likely 8 mph NNW 67%
Sunday 66°F Chance Rain Showers then Chance Showers And Thunderstorms 9 to 13 mph NNE 48%
Sunday Night 57°F Slight Chance Showers And Thunderstorms then Showers And Thunderstorms Likely 13 mph NE 62%
Monday 61°F Rain Showers Likely 13 mph NE 62%
Monday Night 52°F Rain Showers Likely 12 mph NE 60%
Tuesday 59°F Slight Chance Rain Showers then Partly Sunny 10 mph NE 19%
Tuesday Night 48°F Partly Cloudy 3 to 8 mph NE 3%
Wednesday 64°F Sunny 6 mph ENE 1%
Wednesday Night 52°F Partly Cloudy 5 mph E 4%
Thursday 65°F Slight Chance Rain Showers 5 mph E 18%
Thursday Night 56°F Mostly Cloudy 3 mph E 7%
Friday 67°F Partly Sunny 2 to 6 mph E 7%

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

Growing snapshot for Knoxville, IA

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

Explore more for Knoxville, IA: full frost dates · planting calendar · Iowa frost dates

Climate data from the nearest NOAA station, Knoxville, Ia (1.5 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.