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Marathon, IA Weather & Growing Conditions

Local forecast, frost dates, hardiness zone and planting guidance for Marathon, a city in Buena Vista County, Iowa.

Today
71°F
Areas Of Fog
Areas of fog and a chance of rain showers before 8am, then a chance of rain showers and patchy fog between 8am and 10am, then patchy fog and a slight chance of rain showers between 10am and 2pm. Cloudy. High near 71, with temperatures falling to around 67 in the afternoon. North wind 5 to 10 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.

7-day forecast for Marathon

WhenTempForecastWindPrecip
Today 71°F Areas Of Fog 5 to 10 mph N 51%
Tonight 57°F Slight Chance Rain Showers then Cloudy 10 mph NNE 17%
Sunday 66°F Cloudy then Slight Chance Rain Showers 15 mph NE 18%
Sunday Night 52°F Rain Showers Likely 10 to 15 mph ENE 56%
Monday 60°F Rain Showers Likely 5 to 10 mph ENE 56%
Monday Night 47°F Chance Rain Showers then Mostly Cloudy 5 mph ENE 40%
Tuesday 61°F Mostly Sunny 5 mph E 10%
Tuesday Night 43°F Partly Cloudy 0 to 5 mph ESE 1%
Wednesday 65°F Mostly Sunny 0 to 5 mph SE 2%
Wednesday Night 48°F Partly Cloudy then Slight Chance Rain Showers 0 to 5 mph SE 15%
Thursday 67°F Slight Chance Rain Showers 0 to 5 mph SE 18%
Thursday Night 52°F Mostly Cloudy 0 to 5 mph SE 13%
Friday 70°F Partly Sunny 5 mph SE 13%
Friday Night 54°F Mostly Cloudy 5 mph SE 14%

Forecast source: National Weather Service (api.weather.gov) for Marathon (42.860, -94.983). Updated through the day.

Growing snapshot for Marathon

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

More local growing data for Marathon: nearby ZIP 50565 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Sioux Rapids 4 E, Ia (4.1 mi from Marathon). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.