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Onawa, IA Weather & Growing Conditions

Today
74°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 1pm, then patchy smoke and a chance of showers and thunderstorms between 1pm and 2pm, then patchy smoke and showers and thunderstorms likely between 2pm and 4pm, then patchy smoke and a chance of showers and thunderstorms between 4pm and 5pm, then patchy smoke and a slight chance of showers and thunderstorms. Mostly cloudy. High near 74, with temperatures falling to around 72 in the afternoon. North wind around 13 mph, with gusts as high as 22 mph. Chance of precipitation is 70%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Today 74°F Chance Showers And Thunderstorms 13 mph N 71%
Tonight 58°F Patchy Smoke 2 to 10 mph NNE 48%
Wednesday 74°F Patchy Smoke 5 mph NE 19%
Wednesday Night 54°F Mostly Clear 1 to 5 mph SE 2%
Thursday 81°F Sunny 1 to 8 mph SSE 1%
Thursday Night 62°F Mostly Clear 5 to 8 mph SSE 3%
Friday 86°F Sunny 5 to 10 mph S 3%
Friday Night 67°F Mostly Clear 5 to 9 mph S 9%
Saturday 90°F Sunny 5 to 17 mph S 3%
Saturday Night 70°F Mostly Clear 10 to 17 mph S 13%
Sunday 90°F Mostly Sunny 9 to 13 mph SSE 10%
Sunday Night 71°F Partly Cloudy then Slight Chance Showers And Thunderstorms 10 to 15 mph SSE 18%
Monday 90°F Slight Chance Showers And Thunderstorms then Mostly Sunny 10 to 17 mph SE 18%
Monday Night 71°F Partly Cloudy then Slight Chance Showers And Thunderstorms 10 to 17 mph E 17%

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

Growing snapshot for Onawa, IA

Last spring frost
May 1
First fall frost
Oct 3
Growing season
154 days
Hardiness zone
5a

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

Climate data from the nearest NOAA station, Onawa 3Nw, Ia (3.9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.