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Monticello, IA Weather & Growing Conditions

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

Overnight
65°F
Patchy Fog
Patchy fog and occasional showers and thunderstorms. Cloudy. Low around 65, with temperatures rising to around 67 overnight. East wind around 5 mph. Chance of precipitation is 80%. New rainfall amounts between a half and three quarters of an inch possible.

7-day forecast for Monticello

WhenTempForecastWindPrecip
Overnight 65°F Patchy Fog 5 mph E 77%
Saturday 79°F Patchy Fog 5 to 10 mph S 93%
Saturday Night 60°F Showers And Thunderstorms Likely 5 to 10 mph NW 71%
Sunday 67°F Chance Rain Showers 10 to 15 mph NE 49%
Sunday Night 53°F Chance Rain Showers 10 to 15 mph NE 39%
Monday 63°F Chance Rain Showers 15 mph NE 41%
Monday Night 48°F Chance Rain Showers 10 mph NE 40%
Tuesday 62°F Chance Rain Showers then Partly Sunny 10 mph NE 40%
Tuesday Night 45°F Partly Cloudy 5 to 10 mph NE 5%
Wednesday 65°F Mostly Sunny 5 to 10 mph NE 1%
Wednesday Night 48°F Partly Cloudy 0 to 5 mph NE 1%
Thursday 66°F Mostly Sunny 0 to 5 mph NE 7%
Thursday Night 51°F Partly Cloudy 0 mph 5%
Friday 69°F Mostly Sunny 0 to 5 mph E 5%

Forecast source: National Weather Service (api.weather.gov) for Monticello (42.230, -91.186). Updated through the day.

Growing snapshot for Monticello

Last spring frost
May 1
First fall frost
Oct 4
Growing season
154 days
Hardiness zone
5a

More local growing data for Monticello: nearby ZIP 52310 weather · frost dates · planting calendar · Iowa frost dates

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Climate data from the nearest NOAA station, Anamosa 1 Wnw, Ia (9 mi from Monticello). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.