Winthrop, IA Weather & Growing Conditions
Overnight
50°F
Slight Chance Rain Showers
A slight chance of rain showers. Mostly cloudy. Low around 50, with temperatures rising to around 53 overnight. Southwest wind 10 to 15 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 50°F | Slight Chance Rain Showers | 10 to 15 mph SW | 24% |
| Wednesday | 51°F | Chance Rain Showers | 15 mph W | 48% |
| Wednesday Night | 44°F | Chance Rain Showers | 15 mph W | 42% |
| Thursday | 52°F | Chance Rain Showers | 10 to 15 mph NW | 39% |
| Thursday Night | 37°F | Mostly Cloudy | 10 mph N | 13% |
| Friday | 48°F | Mostly Sunny | 5 to 10 mph N | 1% |
| Friday Night | 29°F | Mostly Clear | 0 to 5 mph N | 0% |
| Saturday | 50°F | Sunny | 0 to 5 mph NW | 1% |
| Saturday Night | 34°F | Mostly Clear | 5 mph W | 1% |
| Sunday | 54°F | Sunny | 5 to 10 mph W | 3% |
| Sunday Night | 35°F | Clear | 5 mph SW | 0% |
| Monday | 61°F | Sunny | 5 to 10 mph SW | 0% |
| Monday Night | 40°F | Mostly Clear | 5 mph W | 0% |
| Tuesday | 59°F | Sunny | 5 mph NW | 0% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Winthrop, IA
Last spring frost
Apr 30
First fall frost
Oct 7
Growing season
159 days
Hardiness zone
5a
Explore more for Winthrop, IA: full frost dates · planting calendar · Iowa frost dates
Climate data from the nearest NOAA station, Independence #1, Ia (10.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.