Duncan, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Duncan, a community in Hancock County, Iowa.
Today
71°F
Patchy Fog
Patchy fog and a chance of showers and thunderstorms. Mostly cloudy. High near 71, with temperatures falling to around 69 in the afternoon. North wind around 9 mph. Chance of precipitation is 50%. New rainfall amounts less than a tenth of an inch possible.
7-day forecast for Duncan
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 71°F | Patchy Fog | 9 mph N | 45% |
| Tonight | 55°F | Slight Chance Rain Showers then Cloudy | 9 to 13 mph NNE | 21% |
| Sunday | 66°F | Mostly Cloudy | 15 mph NE | 10% |
| Sunday Night | 50°F | Chance Rain Showers | 13 mph ENE | 28% |
| Monday | 60°F | Chance Rain Showers | 9 to 13 mph ENE | 38% |
| Monday Night | 45°F | Chance Rain Showers then Mostly Cloudy | 5 to 8 mph ENE | 36% |
| Tuesday | 61°F | Mostly Sunny | 5 to 8 mph E | 8% |
| Tuesday Night | 42°F | Mostly Clear | 2 to 6 mph ESE | 1% |
| Wednesday | 64°F | Sunny | 5 mph ESE | 1% |
| Wednesday Night | 47°F | Partly Cloudy then Slight Chance Rain Showers | 3 mph ESE | 15% |
| Thursday | 65°F | Slight Chance Rain Showers then Partly Sunny | 5 mph SE | 15% |
| Thursday Night | 50°F | Mostly Cloudy | 2 mph SE | 4% |
| Friday | 68°F | Partly Sunny | 2 to 6 mph SE | 6% |
| Friday Night | 52°F | Mostly Cloudy | 5 mph SE | 12% |
Forecast source: National Weather Service (api.weather.gov) for Duncan (43.108, -93.702). Updated through the day.
Growing snapshot for Duncan
Last spring frost
Apr 29
First fall frost
Oct 7
Growing season
161 days
Hardiness zone
5a
More local growing data for Duncan: nearby ZIP 50438 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Britt 3E, Ia (6.4 mi from Duncan). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.