Union, KY Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union, a city in Boone County, Kentucky.
This Afternoon
83°F
Mostly Cloudy
Mostly cloudy, with a high near 83. Northeast wind around 9 mph.
7-day forecast for Union
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 83°F | Mostly Cloudy | 9 mph NE | 8% |
| Tonight | 64°F | Partly Cloudy | 5 to 9 mph NE | 9% |
| Saturday | 85°F | Patchy Fog then Slight Chance Showers And Thunderstorms | 5 mph S | 41% |
| Saturday Night | 69°F | Chance Showers And Thunderstorms | 6 mph SE | 46% |
| Sunday | 86°F | Mostly Sunny then Chance Showers And Thunderstorms | 7 mph SW | 29% |
| Sunday Night | 65°F | Chance Showers And Thunderstorms | 6 to 9 mph N | 34% |
| Monday | 79°F | Chance Showers And Thunderstorms | 9 mph NE | 46% |
| Monday Night | 61°F | Chance Showers And Thunderstorms | 8 to 12 mph NE | 50% |
| Tuesday | 74°F | Chance Rain Showers | 9 mph NE | 40% |
| Tuesday Night | 60°F | Chance Showers And Thunderstorms | 6 to 10 mph NE | 40% |
| Wednesday | 71°F | Chance Rain Showers then Slight Chance Showers And Thunderstorms | 8 mph N | 37% |
| Wednesday Night | 58°F | Slight Chance Showers And Thunderstorms then Mostly Cloudy | 5 to 8 mph N | 21% |
| Thursday | 72°F | Partly Sunny | 8 mph N | 11% |
| Thursday Night | 57°F | Partly Cloudy | 5 to 8 mph N | 11% |
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 Sep 18, 2026.