Union, LA Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union, a community in St. James County, Louisiana.
Today
95°F
Sunny
Sunny. High near 95, with temperatures falling to around 93 in the afternoon. West wind around 0 mph.
7-day forecast for Union
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 95°F | Sunny | 0 mph | 7% |
| Tonight | 75°F | Mostly Clear | 0 mph | 9% |
| Wednesday | 96°F | Sunny then Chance Showers And Thunderstorms | 0 to 5 mph W | 27% |
| Wednesday Night | 74°F | Mostly Clear | 0 to 5 mph S | 9% |
| Thursday | 95°F | Sunny then Chance Showers And Thunderstorms | 0 to 5 mph SE | 38% |
| Thursday Night | 74°F | Chance Showers And Thunderstorms then Mostly Clear | 0 mph | 38% |
| Friday | 94°F | Sunny then Chance Showers And Thunderstorms | 0 to 5 mph E | 28% |
| Friday Night | 74°F | Chance Showers And Thunderstorms then Mostly Clear | 0 to 5 mph E | 28% |
| Saturday | 94°F | Mostly Sunny then Chance Showers And Thunderstorms | 0 to 5 mph E | 35% |
| Saturday Night | 75°F | Chance Showers And Thunderstorms then Partly Cloudy | 0 to 5 mph NE | 35% |
| Sunday | 93°F | Showers And Thunderstorms Likely | 0 to 5 mph E | 61% |
| Sunday Night | 75°F | Showers And Thunderstorms Likely | 0 to 5 mph SE | 61% |
| Monday | 93°F | Showers And Thunderstorms Likely | 0 to 5 mph SE | 72% |
| Monday Night | 75°F | Showers And Thunderstorms Likely | 0 mph | 72% |
Forecast source: National Weather Service (api.weather.gov) for Union (30.086, -90.889). Updated through the day.
Growing snapshot for Union
Last spring frost
Feb 21
First fall frost
Dec 5
Growing season
291 days
Hardiness zone
9a
More local growing data for Union: nearby ZIP 70086 weather · frost dates · planting calendar · Louisiana frost dates
Nearby towns & communities
Convent
Gramercy
Grand Point
Hester
Kraemer
Lutcher
Moonshine
North Vacherie
Paulina
Pleasure Bend
Romeville
South Vacherie
St. James
Welcome
Climate data from the nearest NOAA station, Donaldsonville 4 Sw, La (10 mi from Union). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.