Union, KY Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union, a city in Boone County, Kentucky.
Today
84°F
Sunny
Sunny, with a high near 84. Northeast wind around 6 mph.
7-day forecast for Union
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 84°F | Sunny | 6 mph NE | 0% |
| Tonight | 65°F | Partly Cloudy | 3 mph NE | 2% |
| Wednesday | 86°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 mph NW | 21% |
| Wednesday Night | 68°F | Partly Cloudy | 3 mph SW | 3% |
| Thursday | 86°F | Mostly Sunny then Chance Showers And Thunderstorms | 2 to 7 mph SW | 26% |
| Thursday Night | 69°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 5 mph S | 56% |
| Friday | 84°F | Showers And Thunderstorms Likely | 3 to 8 mph SW | 66% |
| Friday Night | 67°F | Showers And Thunderstorms Likely | 5 mph SW | 66% |
| Saturday | 84°F | Chance Showers And Thunderstorms | 3 to 7 mph SW | 36% |
| Saturday Night | 68°F | Chance Showers And Thunderstorms then Partly Cloudy | 5 mph SW | 32% |
| Sunday | 86°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 to 8 mph SW | 16% |
| Sunday Night | 70°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 6 mph SW | 16% |
| Monday | 88°F | Slight Chance Rain Showers then Slight Chance Showers And Thunderstorms | 6 to 9 mph SW | 21% |
| Monday Night | 70°F | Chance Showers And Thunderstorms | 6 mph SW | 26% |
Forecast source: National Weather Service (api.weather.gov) for Union (38.947, -84.674). Updated through the day.
Growing snapshot for Union
Last spring frost
Apr 18
First fall frost
Oct 25
Growing season
188 days
Hardiness zone
6b
More local growing data for Union: nearby ZIP 41042 weather · frost dates · planting calendar · Kentucky frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Cincinnati Northern Ky Ap, Ky (4.1 mi from Union). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.