Union, MO Weather & Growing Conditions
Tonight
70°F
Slight Chance Showers And Thunderstorms then Mostly Clear
A slight chance of showers and thunderstorms before 8pm. Mostly clear, with a low around 70. Heat index values as high as 101. South wind around 1 mph. Chance of precipitation is 20%.
7-day forecast
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Tonight | 70°F | Slight Chance Showers And Thunderstorms then Mostly Clear | 1 mph S | 21% |
| Saturday | 97°F | Partly Sunny | 1 to 5 mph SW | 4% |
| Saturday Night | 71°F | Partly Cloudy | 2 mph SW | 3% |
| Sunday | 92°F | Mostly Sunny then Slight Chance Showers And Thunderstorms | 3 mph W | 19% |
| Sunday Night | 64°F | Chance Showers And Thunderstorms then Showers And Thunderstorms Likely | 2 mph N | 67% |
| Monday | 79°F | Showers And Thunderstorms Likely | 1 to 5 mph N | 68% |
| Monday Night | 58°F | Showers And Thunderstorms Likely then Slight Chance Showers And Thunderstorms | 5 mph N | 67% |
| Tuesday | 71°F | Slight Chance Rain Showers then Mostly Cloudy | 6 mph N | 24% |
| Tuesday Night | 52°F | Mostly Cloudy | 1 to 6 mph N | 5% |
| Wednesday | 73°F | Mostly Sunny | 3 mph N | 1% |
| Wednesday Night | 52°F | Partly Cloudy | 2 mph N | 1% |
| Thursday | 75°F | Mostly Sunny | 0 to 3 mph N | 3% |
| Thursday Night | 55°F | Partly Cloudy | 2 mph N | 3% |
| Friday | 75°F | Mostly Sunny | 0 to 3 mph NE | 9% |
Forecast source: National Weather Service (api.weather.gov). Updated through the day.
Growing snapshot for Union, MO
Last spring frost
Apr 11
First fall frost
Oct 23
Growing season
194 days
Hardiness zone
6b
Explore more for Union, MO: full frost dates · planting calendar · Missouri frost dates
Climate data from the nearest NOAA station, Union, Mo (1.8 mi). Frost dates are 1991–2020 averages, not a forecast. Page updated Sep 19, 2026.