Cromwell, IA Weather & Growing Conditions
Tonight
70°F
Mostly Cloudy then Chance Showers And Thunderstorms
A chance of showers and thunderstorms after midnight. Mostly cloudy, with a low around 70. South wind around 10 mph. Chance of precipitation is 40%. New rainfall amounts between a tenth and quarter of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 70°F | Mostly Cloudy then Chance Showers And Thunderstorms | 10 mph S | 42% |
| Saturday | 81°F | Chance Showers And Thunderstorms | 7 to 10 mph WSW | 41% |
| Saturday Night | 63°F | Chance Showers And Thunderstorms | 9 mph N | 48% |
| Sunday | 67°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 8 to 13 mph NNE | 56% |
| Sunday Night | 58°F | Showers And Thunderstorms Likely | 12 mph NE | 56% |
| Monday | 60°F | Rain Showers Likely | 12 mph NE | 58% |
| Monday Night | 52°F | Chance Rain Showers | 7 to 10 mph NE | 53% |
| Tuesday | 59°F | Mostly Cloudy | 9 mph NE | 10% |
| Tuesday Night | 47°F | Mostly Cloudy | 3 to 7 mph ENE | 4% |
| Wednesday | 63°F | Mostly Sunny | 5 mph E | 2% |
| Wednesday Night | 52°F | Mostly Cloudy | 3 mph ESE | 5% |
| Thursday | 65°F | Slight Chance Rain Showers | 5 mph SE | 21% |
| Thursday Night | 55°F | Slight Chance Rain Showers | 3 mph SE | 18% |
| Friday | 66°F | Slight Chance Rain Showers | 6 mph ESE | 17% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Cromwell, IA
Last spring frost
Apr 28
First fall frost
Oct 11
Growing season
164 days
Hardiness zone
5b
Explore more for Cromwell, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Creston 2 Sw, Ia (3.6 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.