Current Sea Water Temperature:
+88.2°F
| Maximum Sea Water Temperature in August: | 90.2°F |
| Minimum Sea Water Temperature in August: | 86.0°F |
| Average water temperature in August: | 87.8°F |
| detailed information | |
Sea Water Temperature for the Last 10 Days:
| August 19 | 88.2°F | August 14 | 87.6°F |
| August 18 | 88.0°F | August 13 | 88.2°F |
| August 17 | 87.6°F | August 12 | 88.2°F |
| August 16 | 87.8°F | August 11 | 88.2°F |
| August 15 | 88.0°F | August 10 | 88.0°F |
When is the Warmest Sea for San Juan?
According to our data for the last three years for San Juan the highest average sea water temperature was in October, September and August.
Average Water Temperature by Month, °F
Sea Water Temperature in October
The average sea surface temperature in October 2025 for San Juan was 89.5°F. The maximum and minimum values were 88.6°F and 90.0°F respectively.
Sea Water Temperature in September
The average sea surface temperature in September 2025 for San Juan was 89.7°F. The maximum and minimum values were 89.2°F and 90.4°F respectively.
Sea Water Temperature in August
The average sea surface temperature in August 2026 for San Juan was 88.0°F. The maximum and minimum values were 87.6°F and 88.4°F respectively.
Puerto Rico Resorts:
NAME
F°
| Aguadilla |  |
+86 |
| Arecibo |  |
+88 |
| Isabella | |
+88 |
| Mayaguez | |
+86 |
| Ponce |  |
+88 |
| San Juan | |
+88 |
Countries:
NAME
POPULARITY
24 Hours Weather Forecast
San Juan
Local time: 07:42
19 aug, wednesday
| 0900 |  |
88°F | NW 9 mph |
| 1200 | |
92°F | W 14 mph |
| 1500 |  |
92°F | W 16 mph |
| 1800 |  |
88°F | W 14 mph |
| 2100 | |
86°F | NW 11 mph |
20 aug, thursday
| 0000 | |
84°F | NW 11 mph |
| 0300 | |
84°F | NW 9 mph |
| 0600 | |
84°F | NW 11 mph |