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St. Joseph, IA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for St. Joseph, a community in Humboldt County, Iowa.

Today
77°F
Showers And Thunderstorms Likely
Showers and thunderstorms likely. Mostly cloudy. High near 77, with temperatures falling to around 73 in the afternoon. North northwest wind 8 to 12 mph. Chance of precipitation is 60%. New rainfall amounts between a tenth and quarter of an inch possible.

7-day forecast for St. Joseph

WhenTempForecastWindPrecip
Today 77°F Showers And Thunderstorms Likely 8 to 12 mph NNW 62%
Tonight 56°F Showers And Thunderstorms Likely then Mostly Cloudy 2 to 7 mph NNW 58%
Wednesday 77°F Partly Sunny 5 mph NNE 2%
Wednesday Night 53°F Mostly Clear 3 mph SSE 2%
Thursday 82°F Sunny 2 to 7 mph S 1%
Thursday Night 60°F Mostly Clear 5 to 8 mph S 2%
Friday 85°F Sunny 5 to 13 mph SSW 9%
Friday Night 65°F Chance Showers And Thunderstorms 6 to 13 mph S 25%
Saturday 89°F Slight Chance Showers And Thunderstorms then Sunny 5 to 15 mph S 15%
Saturday Night 68°F Slight Chance Showers And Thunderstorms 10 to 15 mph SE 26%
Sunday 88°F Chance Showers And Thunderstorms then Mostly Sunny 12 mph SE 26%
Sunday Night 68°F Slight Chance Showers And Thunderstorms 8 to 12 mph SE 31%
Monday 87°F Chance Showers And Thunderstorms then Slight Chance Showers And Thunderstorms 9 to 14 mph E 31%
Monday Night 68°F Slight Chance Showers And Thunderstorms 9 to 15 mph ENE 32%

Forecast source: National Weather Service (api.weather.gov) for St. Joseph (42.912, -94.231). Updated through the day.

Growing snapshot for St. Joseph

Last spring frost
Apr 30
First fall frost
Oct 6
Growing season
160 days
Hardiness zone
5a

More local growing data for St. Joseph: nearby ZIP 50519 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Algona, Ia (11.5 mi from St. Joseph). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.