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Knoxville, IA Weather & Growing Conditions

Today
86°F
Partly Sunny then Chance Showers And Thunderstorms
A chance of showers and thunderstorms after noon. Partly sunny. High near 86, with temperatures falling to around 84 in the afternoon. West northwest wind around 8 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 86°F Partly Sunny then Chance Showers And Thunderstorms 8 mph WNW 32%
Tonight 64°F Showers And Thunderstorms 10 mph NNE 92%
Wednesday 74°F Showers And Thunderstorms Likely 8 mph NNE 92%
Wednesday Night 60°F Showers And Thunderstorms Likely 3 to 8 mph NNE 55%
Thursday 80°F Mostly Sunny 5 mph NE 14%
Thursday Night 62°F Mostly Clear 0 to 3 mph ESE 3%
Friday 85°F Sunny 2 to 7 mph S 6%
Friday Night 67°F Mostly Clear 6 mph SSE 14%
Saturday 89°F Sunny 5 to 9 mph S 10%
Saturday Night 72°F Mostly Clear 12 mph SSW 12%
Sunday 90°F Mostly Sunny 13 mph SSW 12%
Sunday Night 72°F Slight Chance Showers And Thunderstorms 12 mph S 26%
Monday 90°F Chance Showers And Thunderstorms then Mostly Sunny 14 mph SSW 26%
Monday Night 73°F Chance Showers And Thunderstorms 14 mph SSE 26%

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 Aug 4, 2026.