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Jefferson, IA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Jefferson, a city in Greene County, Iowa.

Today
75°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms. Mostly cloudy. High near 75, with temperatures falling to around 72 in the afternoon. North northwest wind 3 to 7 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Jefferson

WhenTempForecastWindPrecip
Today 75°F Chance Showers And Thunderstorms 3 to 7 mph NNW 29%
Tonight 60°F Slight Chance Showers And Thunderstorms 8 mph N 27%
Sunday 66°F Chance Drizzle 10 mph NNE 42%
Sunday Night 55°F Chance Rain Showers 9 mph ENE 46%
Monday 62°F Rain Showers Likely 9 mph ENE 58%
Monday Night 50°F Chance Rain Showers 3 to 7 mph NE 53%
Tuesday 62°F Partly Sunny 6 mph ENE 8%
Tuesday Night 45°F Partly Cloudy 3 mph E 1%
Wednesday 66°F Mostly Sunny 3 mph ESE 1%
Wednesday Night 50°F Partly Cloudy 2 mph ESE 10%
Thursday 67°F Slight Chance Rain Showers 1 to 5 mph SE 18%
Thursday Night 53°F Mostly Cloudy 2 mph ESE 9%
Friday 69°F Mostly Cloudy 1 to 6 mph ESE 9%
Friday Night 55°F Mostly Cloudy 3 mph SE 11%

Forecast source: National Weather Service (api.weather.gov) for Jefferson (42.018, -94.379). Updated through the day.

Growing snapshot for Jefferson

Last spring frost
Apr 26
First fall frost
Oct 9
Growing season
164 days
Hardiness zone
5b

More local growing data for Jefferson: nearby ZIP 50129 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Jefferson, Ia (1 mi from Jefferson). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.