Defiance, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Defiance, a city in Shelby County, Iowa.
Tonight
58°F
Chance Rain Showers
A chance of rain showers. Cloudy. Low around 58, with temperatures rising to around 61 overnight. North northeast wind around 8 mph, with gusts as high as 16 mph. Chance of precipitation is 30%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Defiance
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 58°F | Chance Rain Showers | 8 mph NNE | 26% |
| Sunday | 63°F | Chance Rain Showers | 8 to 12 mph NE | 47% |
| Sunday Night | 53°F | Rain Showers Likely | 9 mph NE | 70% |
| Monday | 57°F | Rain Showers | 9 mph NE | 83% |
| Monday Night | 48°F | Rain Showers Likely then Mostly Cloudy | 3 to 8 mph NE | 63% |
| Tuesday | 60°F | Partly Sunny | 3 to 7 mph ENE | 3% |
| Tuesday Night | 45°F | Partly Cloudy | 1 to 5 mph E | 0% |
| Wednesday | 63°F | Mostly Sunny | 1 to 5 mph ESE | 1% |
| Wednesday Night | 50°F | Mostly Cloudy then Slight Chance Showers And Thunderstorms | 3 mph SE | 21% |
| Thursday | 66°F | Chance Showers And Thunderstorms | 3 to 7 mph SSE | 36% |
| Thursday Night | 55°F | Chance Rain Showers | 1 to 5 mph SE | 25% |
| Friday | 69°F | Slight Chance Rain Showers | 1 to 6 mph ESE | 20% |
| Friday Night | 57°F | Mostly Cloudy then Chance Rain Showers | 3 mph ESE | 26% |
| Saturday | 69°F | Chance Rain Showers | 5 to 9 mph SE | 34% |
Forecast source: National Weather Service (api.weather.gov) for Defiance (41.825, -95.340). Updated through the day.
Growing snapshot for Defiance
Last spring frost
Apr 27
First fall frost
Oct 9
Growing season
165 days
Hardiness zone
5a
More local growing data for Defiance: nearby ZIP 51527 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Harlan, Ia (13.4 mi from Defiance). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 20, 2026.