Onslow, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Onslow, a city in Jones County, Iowa.
Overnight
65°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 2am, then showers and thunderstorms. Mostly cloudy, with a low around 65. Southeast wind 5 to 10 mph. Chance of precipitation is 90%. New rainfall amounts between a half and three quarters of an inch possible.
7-day forecast for Onslow
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 65°F | Chance Showers And Thunderstorms | 5 to 10 mph SE | 87% |
| Saturday | 80°F | Showers And Thunderstorms | 5 mph S | 79% |
| Saturday Night | 62°F | Showers And Thunderstorms | 5 mph N | 77% |
| Sunday | 67°F | Showers And Thunderstorms Likely | 10 mph NE | 65% |
| Sunday Night | 55°F | Rain Showers Likely | 10 mph NE | 59% |
| Monday | 63°F | Chance Rain Showers | 10 mph NE | 53% |
| Monday Night | 50°F | Chance Rain Showers | 5 to 10 mph NE | 53% |
| Tuesday | 62°F | Chance Rain Showers | 5 to 10 mph NE | 40% |
| Tuesday Night | 47°F | Partly Cloudy | 5 mph NE | 6% |
| Wednesday | 66°F | Mostly Sunny | 5 mph NE | 2% |
| Wednesday Night | 50°F | Partly Cloudy | 0 to 5 mph NE | 3% |
| Thursday | 68°F | Mostly Sunny | 0 to 5 mph NE | 6% |
| Thursday Night | 52°F | Partly Cloudy | 0 mph | 6% |
| Friday | 69°F | Mostly Sunny | 0 to 5 mph NE | 5% |
Forecast source: National Weather Service (api.weather.gov) for Onslow (42.107, -91.015). Updated through the day.
Growing snapshot for Onslow
Last spring frost
Apr 28
First fall frost
Oct 10
Growing season
164 days
Hardiness zone
5a
More local growing data for Onslow: nearby ZIP 52321 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Cascade, Ia (10.9 mi from Onslow). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.