Click on a day for an hourly weather forecast
The temperatures in Costa Rica in September are comfortable with low of 17°C and and high up to 22°C.
With more than 22 rainy days, Costa Rica is an incredibly wet during September. Be sure to pack your umbrella and bring along your rubber boots to stay dry. It’s going to be raining cats and dogs this month!
Our weather forecast can give you a great sense of what weather to expect in Costa Rica in September 2025.
If you’re planning to visit Costa Rica in the near future, we highly recommend that you review the 14 day weather forecast for Costa Rica before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 23° / 14° | 4 | 27 | 0 | 92 mm | Perfect | Costa Rica in January |
| February | 24° / 14° | 4 | 25 | 0 | 78 mm | Perfect | Costa Rica in February |
| March | 25° / 15° | 5 | 26 | 0 | 92 mm | Perfect | Costa Rica in March |
| April | 25° / 16° | 13 | 17 | 0 | 231 mm | Good | Costa Rica in April |
| May | 23° / 17° | 24 | 7 | 0 | 749 mm | Good | Costa Rica in May |
| June | 22° / 17° | 26 | 4 | 0 | 855 mm | Ok | Costa Rica in June |
| July | 22° / 17° | 24 | 7 | 0 | 685 mm | Ok | Costa Rica in July |
| August | 22° / 17° | 25 | 6 | 0 | 757 mm | Ok | Costa Rica in August |
| September | 22° / 17° | 28 | 2 | 0 | 793 mm | Awful | Costa Rica in September |
| October | 22° / 17° | 27 | 4 | 0 | 943 mm | Awful | Costa Rica in October |
| November | 22° / 16° | 19 | 11 | 0 | 481 mm | Ok | Costa Rica in November |
| December | 23° / 15° | 9 | 22 | 0 | 186 mm | Good | Costa Rica in December |