Defiance, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Defiance, a city in Shelby County, Iowa.
Overnight
39°F
Slight Chance Rain Showers
A slight chance of rain showers. Cloudy. Low around 39, with temperatures rising to around 43 overnight. Northwest wind around 16 mph, with gusts as high as 25 mph. Chance of precipitation is 20%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Defiance
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 39°F | Slight Chance Rain Showers | 16 mph NW | 20% |
| Wednesday | 48°F | Chance Rain Showers | 13 to 16 mph WNW | 42% |
| Wednesday Night | 37°F | Chance Rain Showers | 13 mph WNW | 28% |
| Thursday | 50°F | Chance Rain Showers then Mostly Cloudy | 12 mph NNW | 25% |
| Thursday Night | 34°F | Mostly Cloudy | 2 to 8 mph N | 1% |
| Friday | 49°F | Mostly Sunny | 3 mph N | 1% |
| Friday Night | 29°F | Partly Cloudy | 0 mph | 0% |
| Saturday | 53°F | Mostly Sunny | 0 to 5 mph SSW | 1% |
| Saturday Night | 33°F | Mostly Clear | 2 mph WSW | 0% |
| Sunday | 58°F | Sunny | 1 to 6 mph WSW | 0% |
| Sunday Night | 37°F | Clear | 5 mph SSW | 0% |
| Monday | 63°F | Sunny | 5 to 9 mph SW | 0% |
| Monday Night | 39°F | Mostly Clear | 3 mph WNW | 0% |
| Tuesday | 63°F | Mostly Sunny | 1 to 5 mph NNW | 0% |
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 Nov 4, 2026.