Union Valley, TX Weather & Growing Conditions
Local forecast, frost dates, hardiness zone and planting guidance for Union Valley, a city in Rockwall County, Texas.
Today
101°F
Sunny
Sunny, with a high near 101. Heat index values as high as 101. South wind 0 to 10 mph.
7-day forecast for Union Valley
| When | Temp | Forecast | Wind | Precip |
|---|---|---|---|---|
| Today | 101°F | Sunny | 0 to 10 mph S | 0% |
| Tonight | 76°F | Mostly Clear | 5 mph SSE | 0% |
| Wednesday | 101°F | Sunny | 5 to 10 mph SSW | 0% |
| Wednesday Night | 76°F | Mostly Clear | 5 mph SSE | 0% |
| Thursday | 100°F | Sunny | 5 to 10 mph SSW | 1% |
| Thursday Night | 77°F | Mostly Clear | 5 mph SSE | 2% |
| Friday | 97°F | Sunny | 5 mph S | 9% |
| Friday Night | 76°F | Mostly Clear | 5 mph SSE | 9% |
| Saturday | 97°F | Sunny | 5 mph S | 9% |
| Saturday Night | 75°F | Mostly Clear | 5 mph SSE | 9% |
| Sunday | 98°F | Sunny | 5 to 10 mph S | 7% |
| Sunday Night | 75°F | Mostly Clear | 5 mph SSE | 7% |
| Monday | 98°F | Sunny | 5 to 10 mph S | 7% |
| Monday Night | 76°F | Mostly Clear | 10 mph S | 7% |
Forecast source: National Weather Service (api.weather.gov) for Union Valley (32.929, -96.249). Updated through the day.
Growing snapshot for Union Valley
Last spring frost
Mar 10
First fall frost
Nov 19
Growing season
254 days
Hardiness zone
8b
More local growing data for Union Valley: nearby ZIP 75189 weather · frost dates · planting calendar · Texas frost dates
Nearby towns & communities
Climate data from the nearest NOAA station, Lavon Dam, Tx (12 mi from Union Valley). Frost dates are 1991–2020 averages, not a forecast. Page updated Aug 4, 2026.