Union, KY Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union, a city in Boone County, Kentucky.
This Afternoon
77°F
Sunny
Sunny, with a high near 77. South wind around 12 mph.
7-day forecast for Union
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 77°F | Sunny | 12 mph S | 1% |
| Tonight | 62°F | Mostly Cloudy then Showers And Thunderstorms | 8 to 14 mph SE | 86% |
| Wednesday | 68°F | Showers And Thunderstorms | 9 to 15 mph S | 98% |
| Wednesday Night | 51°F | Slight Chance Rain Showers then Mostly Cloudy | 8 mph SW | 18% |
| Thursday | 66°F | Mostly Sunny | 6 to 10 mph SW | 0% |
| Thursday Night | 46°F | Partly Cloudy | 2 to 6 mph SW | 0% |
| Friday | 62°F | Partly Sunny | 2 to 8 mph NW | 8% |
| Friday Night | 42°F | Mostly Cloudy | 7 mph NW | 8% |
| Saturday | 56°F | Mostly Sunny | 7 mph NW | 8% |
| Saturday Night | 37°F | Partly Cloudy | 5 mph NW | 5% |
| Sunday | 58°F | Mostly Sunny | 3 to 8 mph W | 7% |
| Sunday Night | 37°F | Mostly Clear | 6 mph W | 11% |
| Monday | 60°F | Sunny | 3 to 8 mph W | 11% |
| Monday Night | 39°F | Mostly Clear | 7 mph SW | 8% |
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 Nov 3, 2026.