Click on a day for an hourly weather forecast
The temperatures in San Luis in September are comfortable with low of 11°C and and high up to 21°C.
You can expect about 3 to 8 days of rain in San Luis 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 San Luis in September 2026.
If you’re planning to visit San Luis in the near future, we highly recommend that you review the 14 day weather forecast for San Luis before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 31° / 20° | 7 | 24 | 0 | 130 mm | Ok | San Luis in January |
| February | 30° / 19° | 7 | 22 | 0 | 126 mm | Ok | San Luis in February |
| March | 27° / 17° | 5 | 26 | 0 | 87 mm | Perfect | San Luis in March |
| April | 23° / 14° | 4 | 26 | 0 | 65 mm | Perfect | San Luis in April |
| May | 19° / 10° | 2 | 29 | 0 | 22 mm | Good | San Luis in May |
| June | 16° / 7° | 0 | 29 | 0 | 8 mm | Good | San Luis in June |
| July | 15° / 6° | 0 | 30 | 0 | 4 mm | Good | San Luis in July |
| August | 18° / 9° | 0 | 30 | 0 | 7 mm | Good | San Luis in August |
| September | 21° / 11° | 3 | 27 | 0 | 34 mm | Good | San Luis in September |
| October | 24° / 13° | 5 | 26 | 0 | 92 mm | Perfect | San Luis in October |
| November | 27° / 16° | 8 | 22 | 0 | 126 mm | Good | San Luis in November |
| December | 30° / 19° | 7 | 24 | 0 | 108 mm | Ok | San Luis in December |