Monticello, IA Weather & Growing Conditions
Today
79°F
Occasional Showers And Thunderstorms then Chance Showers And Thunderstorms
Occasional showers and thunderstorms before 11am, then a chance of showers and thunderstorms between 11am and 1pm, then a chance of showers and thunderstorms between 1pm and 2pm, then showers and thunderstorms likely between 2pm and 4pm, then a chance of showers and thunderstorms between 4pm and 5pm, then showers and thunderstorms likely. Some of the storms could produce heavy rain. Mostly cloudy, with a high near 79. South wind 5 to 10 mph. Chance of precipitation is 90%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 79°F | Occasional Showers And Thunderstorms then Chance Showers And Thunderstorms | 5 to 10 mph S | 89% |
| Tonight | 61°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 | 54°F | Chance Rain Showers | 10 to 15 mph NE | 40% |
| Monday | 63°F | Chance Rain Showers | 15 mph NE | 41% |
| Monday Night | 49°F | Chance Rain Showers | 5 to 10 mph NE | 39% |
| Tuesday | 62°F | Chance Rain Showers then Partly Sunny | 10 mph NE | 39% |
| Tuesday Night | 45°F | Partly Cloudy | 5 to 10 mph NE | 5% |
| Wednesday | 66°F | Mostly Sunny | 5 mph NE | 1% |
| Wednesday Night | 49°F | Partly Cloudy | 0 to 5 mph NE | 1% |
| Thursday | 67°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 | 6% |
| Friday Night | 52°F | Partly Cloudy | 0 mph | 6% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Monticello, IA
Last spring frost
May 1
First fall frost
Oct 4
Growing season
154 days
Hardiness zone
5a
Explore more for Monticello, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Anamosa 1 Wnw, Ia (9 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.