Click on a day for an hourly weather forecast
The temperatures in Union City in September are comfortable with low of 15°C and and high up to 28°C.
You can expect up to 3 rainy days in Union City during the month of September.
Our weather forecast can give you a great sense of what weather to expect in Union City in September 2025.
If you’re planning to visit Union City in the near future, we highly recommend that you review the 14 day weather forecast for Union City before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 16° / 7° | 4 | 27 | 0 | 36 mm | Good | Union City in January |
| February | 17° / 7° | 3 | 25 | 0 | 36 mm | Good | Union City in February |
| March | 18° / 7° | 3 | 28 | 0 | 39 mm | Good | Union City in March |
| April | 20° / 8° | 2 | 28 | 0 | 17 mm | Good | Union City in April |
| May | 22° / 10° | 1 | 30 | 0 | 8 mm | Good | Union City in May |
| June | 26° / 13° | 1 | 29 | 0 | 4 mm | Perfect | Union City in June |
| July | 28° / 14° | 0 | 31 | 0 | 1 mm | Perfect | Union City in July |
| August | 28° / 15° | 0 | 31 | 0 | 1 mm | Perfect | Union City in August |
| September | 28° / 15° | 0 | 30 | 0 | 3 mm | Perfect | Union City in September |
| October | 24° / 13° | 1 | 30 | 0 | 16 mm | Perfect | Union City in October |
| November | 19° / 10° | 2 | 28 | 0 | 23 mm | Good | Union City in November |
| December | 15° / 7° | 4 | 27 | 0 | 34 mm | Good | Union City in December |