Click on a day for an hourly weather forecast
The weather in Mcallen in September is very hot. The average temperatures are between 26°C and 34°C, drinking water regularly is advisable.
You can expect about 3 to 8 days of rain in Mcallen during the month of September. It’s a good idea to bring along your umbrella so that you don’t get caught in poor weather.
Our weather forecast can give you a great sense of what weather to expect in Mcallen in September 2025.
If you’re planning to visit Mcallen in the near future, we highly recommend that you review the 14 day weather forecast for Mcallen before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 21° / 13° | 3 | 28 | 0 | 46 mm | Good | Mcallen in January |
| February | 24° / 15° | 2 | 26 | 0 | 29 mm | Perfect | Mcallen in February |
| March | 28° / 18° | 2 | 29 | 0 | 34 mm | Perfect | Mcallen in March |
| April | 31° / 20° | 3 | 27 | 0 | 41 mm | Good | Mcallen in April |
| May | 33° / 23° | 4 | 27 | 0 | 74 mm | Good | Mcallen in May |
| June | 35° / 25° | 5 | 25 | 0 | 90 mm | Ok | Mcallen in June |
| July | 36° / 26° | 3 | 28 | 0 | 80 mm | Ok | Mcallen in July |
| August | 37° / 27° | 3 | 28 | 0 | 47 mm | Ok | Mcallen in August |
| September | 34° / 26° | 7 | 23 | 0 | 137 mm | Bad | Mcallen in September |
| October | 31° / 22° | 3 | 28 | 0 | 48 mm | Good | Mcallen in October |
| November | 26° / 18° | 3 | 27 | 0 | 51 mm | Perfect | Mcallen in November |
| December | 23° / 15° | 3 | 28 | 0 | 52 mm | Perfect | Mcallen in December |