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Castana, IA Weather & Growing Conditions

Overnight
66°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms. Mostly cloudy. Low around 66, with temperatures rising to around 69 overnight. Northwest wind around 7 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast

WhenTempForecastWindPrecip
Overnight 66°F Slight Chance Showers And Thunderstorms 7 mph NW 18%
Tuesday 73°F Slight Chance Showers And Thunderstorms then Chance Showers And Thunderstorms 8 to 12 mph N 74%
Tuesday Night 58°F Patchy Smoke 2 to 8 mph NE 71%
Wednesday 72°F Patchy Smoke 5 mph ENE 17%
Wednesday Night 54°F Mostly Clear 1 to 5 mph ESE 2%
Thursday 79°F Mostly Sunny 1 to 7 mph SSE 1%
Thursday Night 63°F Mostly Clear 7 mph SSE 3%
Friday 84°F Sunny 5 to 9 mph S 3%
Friday Night 67°F Mostly Clear 5 to 8 mph S 9%
Saturday 89°F Sunny 5 to 14 mph S 3%
Saturday Night 70°F Slight Chance Showers And Thunderstorms 9 to 14 mph SSE 15%
Sunday 89°F Mostly Sunny 10 mph SSE 11%
Sunday Night 71°F Partly Cloudy then Slight Chance Showers And Thunderstorms 13 mph SSE 20%
Monday 89°F Slight Chance Showers And Thunderstorms then Mostly Sunny 10 to 14 mph SE 20%

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

Growing snapshot for Castana, IA

Last spring frost
Apr 25
First fall frost
Oct 12
Growing season
170 days
Hardiness zone
5b

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

Climate data from the nearest NOAA station, Castana Exp Farm, Ia (5.7 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.