Union, MO Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union, a city in Franklin County, Missouri.
This Afternoon
75°F
Light Rain
Rain and a slight chance of thunderstorms. Cloudy. High near 75, with temperatures falling to around 66 in the afternoon. South wind around 12 mph, with gusts as high as 23 mph. Chance of precipitation is 90%.
7-day forecast for Union
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| This Afternoon | 75°F | Light Rain | 12 mph S | 90% |
| Tonight | 48°F | Light Rain Likely | 3 to 8 mph SW | 67% |
| Wednesday | 62°F | Mostly Cloudy | 5 to 9 mph W | 2% |
| Wednesday Night | 37°F | Partly Cloudy | 2 mph SW | 0% |
| Thursday | 66°F | Sunny | 2 to 6 mph W | 3% |
| Thursday Night | 37°F | Mostly Cloudy | 2 mph NW | 12% |
| Friday | 57°F | Mostly Cloudy | 2 to 6 mph NW | 3% |
| Friday Night | 34°F | Mostly Cloudy | 1 mph N | 3% |
| Saturday | 57°F | Partly Sunny | 1 mph NW | 0% |
| Saturday Night | 31°F | Partly Cloudy | 0 mph | 2% |
| Sunday | 62°F | Sunny | 0 to 3 mph NW | 7% |
| Sunday Night | 31°F | Mostly Clear | 1 mph NW | 3% |
| Monday | 67°F | Sunny | 0 to 3 mph W | 2% |
| Monday Night | 35°F | Mostly Clear | 0 mph | 1% |
Forecast source: National Weather Service (api.weather.gov) for Union (38.438, -90.996). Updated through the day.
Growing snapshot for Union
Last spring frost
Apr 11
First fall frost
Oct 23
Growing season
194 days
Hardiness zone
6b
More local growing data for Union: nearby ZIP 63084 weather · frost dates · planting calendar · Missouri frost dates
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Climate data from the nearest NOAA station, Union, Mo (1.8 mi from Union). Frost dates are 1991–2020 averages, not a forecast. Page updated Nov 4, 2026.