Keystone, IA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Keystone, a city in Benton County, Iowa.
Overnight
66°F
Chance Showers And Thunderstorms
A chance of showers and thunderstorms before 4am, then patchy fog and showers and thunderstorms likely. Cloudy, with a low around 66. Southeast wind 5 to 10 mph. Chance of precipitation is 70%. New rainfall amounts between a quarter and half of an inch possible.
7-day forecast for Keystone
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Overnight | 66°F | Chance Showers And Thunderstorms | 5 to 10 mph SE | 72% |
| Saturday | 80°F | Patchy Fog | 5 to 10 mph S | 77% |
| Saturday Night | 61°F | Showers And Thunderstorms Likely | 5 to 10 mph N | 67% |
| Sunday | 67°F | Rain Showers Likely | 10 to 15 mph NE | 59% |
| Sunday Night | 55°F | Chance Rain Showers | 10 to 15 mph NE | 47% |
| Monday | 63°F | Chance Rain Showers | 10 to 15 mph NE | 47% |
| Monday Night | 50°F | Chance Rain Showers | 10 mph NE | 36% |
| Tuesday | 61°F | Chance Rain Showers then Partly Sunny | 10 mph NE | 27% |
| Tuesday Night | 46°F | Mostly Clear | 5 mph NE | 4% |
| Wednesday | 66°F | Sunny | 5 mph NE | 0% |
| Wednesday Night | 50°F | Partly Cloudy | 0 to 5 mph NE | 3% |
| Thursday | 67°F | Partly Sunny | 5 mph E | 8% |
| Thursday Night | 53°F | Partly Cloudy | 0 to 5 mph E | 6% |
| Friday | 69°F | Mostly Sunny | 5 mph E | 6% |
Forecast source: National Weather Service (api.weather.gov) for Keystone (41.999, -92.198). Updated through the day.
Growing snapshot for Keystone
Last spring frost
Apr 28
First fall frost
Oct 10
Growing season
165 days
Hardiness zone
5a
More local growing data for Keystone: nearby ZIP 52249 weather · frost dates · planting calendar · Iowa frost dates
Nearby towns & communities
Atkins
Belle Plaine
Blairstown
Dysart
Garrison
Luzerne
Mount Auburn
Newhall
Norway
Shellsburg
Urbana
Van Horne
Vinton
Walford
Watkins
Climate data from the nearest NOAA station, Belle Plaine, Ia (9.7 mi from Keystone). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.