Click on a day for an hourly weather forecast
The weather in San Juan in August is very hot. The average temperatures are between 25°C and 29°C, drinking water regularly is advisable.
You can expect rain for roughly half of the month of August in San Juan. We’re expecting roughly 8 to 15 days of rain, so your rubber boots and umbrella are going to see plenty of use this month if you’re keen on staying dry.
Our weather forecast can give you a great sense of what weather to expect in San Juan in August 2025.
If you’re planning to visit San Juan in the near future, we highly recommend that you review the 14 day weather forecast for San Juan before you arrive.
| Month | Temperatures | Rainy Days | Dry Days | Snowy Days | Rainfall | Weather | More details |
|---|---|---|---|---|---|---|---|
| January | 27° / 22° | 2 | 29 | 0 | 62 mm | Perfect | San Juan in January |
| February | 27° / 22° | 2 | 26 | 0 | 58 mm | Perfect | San Juan in February |
| March | 27° / 22° | 3 | 28 | 0 | 74 mm | Perfect | San Juan in March |
| April | 28° / 23° | 4 | 26 | 0 | 91 mm | Perfect | San Juan in April |
| May | 28° / 24° | 8 | 23 | 0 | 152 mm | Good | San Juan in May |
| June | 29° / 25° | 5 | 25 | 0 | 100 mm | Good | San Juan in June |
| July | 29° / 25° | 5 | 26 | 0 | 119 mm | Good | San Juan in July |
| August | 29° / 25° | 8 | 23 | 0 | 184 mm | Ok | San Juan in August |
| September | 30° / 26° | 9 | 21 | 0 | 197 mm | Ok | San Juan in September |
| October | 29° / 25° | 10 | 21 | 0 | 185 mm | Ok | San Juan in October |
| November | 28° / 24° | 8 | 22 | 0 | 174 mm | Good | San Juan in November |
| December | 27° / 23° | 4 | 27 | 0 | 82 mm | Perfect | San Juan in December |