Promise City, IA Weather & Growing Conditions
Today
89°F
Mostly Sunny then Slight Chance Showers And Thunderstorms
A slight chance of showers and thunderstorms after 5pm. Mostly sunny. High near 89, with temperatures falling to around 87 in the afternoon. West southwest wind 3 to 7 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 |
|---|---|---|---|---|
| Today | 89°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 to 7 mph WSW | 19% |
| Tonight | 66°F | Showers And Thunderstorms Likely | 5 to 8 mph NNE | 71% |
| Wednesday | 77°F | Chance Showers And Thunderstorms | 7 mph NE | 93% |
| Wednesday Night | 61°F | Showers And Thunderstorms Likely then Chance Showers And Thunderstorms | 2 to 8 mph NE | 63% |
| Thursday | 82°F | Chance Showers And Thunderstorms then Mostly Sunny | 3 mph NE | 40% |
| Thursday Night | 62°F | Mostly Clear | 2 mph ESE | 4% |
| Friday | 86°F | Sunny | 1 to 5 mph S | 7% |
| Friday Night | 67°F | Mostly Clear | 5 mph S | 13% |
| Saturday | 90°F | Sunny | 5 to 10 mph SSW | 9% |
| Saturday Night | 72°F | Mostly Clear | 10 to 15 mph SSW | 9% |
| Sunday | 92°F | Sunny | 13 to 16 mph SSW | 9% |
| Sunday Night | 73°F | Partly Cloudy then Slight Chance Showers And Thunderstorms | 12 to 15 mph SSW | 20% |
| Monday | 93°F | Slight Chance Showers And Thunderstorms then Mostly Sunny | 14 to 18 mph SSW | 20% |
| Monday Night | 72°F | Chance Showers And Thunderstorms | 13 to 18 mph SSW | 26% |
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 Aug 4, 2026.