Promise City, IA Weather & Growing Conditions
Overnight
70°F
Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 3am. Mostly cloudy, with a low around 70. South wind around 8 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 70°F | Slight Chance Showers And Thunderstorms | 8 mph S | 23% |
| Saturday | 84°F | Chance Showers And Thunderstorms | 6 to 10 mph SW | 32% |
| Saturday Night | 64°F | Chance Showers And Thunderstorms then Showers And Thunderstorms | 2 to 6 mph NNW | 77% |
| Sunday | 71°F | Showers And Thunderstorms Likely | 6 to 10 mph NNE | 65% |
| Sunday Night | 58°F | Showers And Thunderstorms Likely | 10 mph NE | 65% |
| Monday | 62°F | Rain Showers Likely | 12 mph NE | 60% |
| Monday Night | 53°F | Chance Rain Showers | 7 to 10 mph NE | 51% |
| Tuesday | 60°F | Slight Chance Rain Showers | 9 mph NE | 18% |
| Tuesday Night | 48°F | Mostly Cloudy | 2 to 6 mph NE | 4% |
| Wednesday | 64°F | Mostly Sunny | 5 mph NE | 1% |
| Wednesday Night | 52°F | Partly Cloudy | 0 to 3 mph ENE | 4% |
| Thursday | 66°F | Partly Sunny | 0 to 3 mph E | 10% |
| Thursday Night | 55°F | Mostly Cloudy then Slight Chance Rain Showers | 1 mph ENE | 15% |
| Friday | 68°F | Slight Chance Rain Showers | 1 to 5 mph E | 15% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Promise City, IA
Last spring frost
Apr 18
First fall frost
Oct 23
Growing season
187 days
Hardiness zone
5b
Explore more for Promise City, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Rathbun Dam, Ia (13.3 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.