Current Sea Water Temperature:
+64.2°F
| Maximum Sea Water Temperature in September: | 70.8°F |
| Minimum Sea Water Temperature in September: | 57.2°F |
| Average water temperature in September: | 63.9°F |
| detailed information | |
Sea Water Temperature for the Last 10 Days:
| September 15 | 64.2°F | September 10 | 67.6°F |
| September 14 | 66.4°F | September 09 | 67.8°F |
| September 13 | 66.4°F | September 08 | 67.2°F |
| September 12 | 66.6°F | September 07 | 68.8°F |
| September 11 | 67.6°F | September 06 | 67.8°F |
When is the Warmest Sea for Portsmouth?
According to our data for the last three years for Portsmouth the highest average sea water temperature was in August, July and September.
Average Water Temperature by Month, °F
Sea Water Temperature in August
The average sea surface temperature in August 2026 for Portsmouth was 69.1°F. The maximum and minimum values were 66.0°F and 74.6°F respectively.
Sea Water Temperature in July
The average sea surface temperature in July 2026 for Portsmouth was 67.5°F. The maximum and minimum values were 64.4°F and 72.4°F respectively.
Sea Water Temperature in September
The average sea surface temperature in September 2026 for Portsmouth was 67.5°F. The maximum and minimum values were 64.2°F and 69.2°F respectively.
USA Resorts:
NAME
F°
| Boston |  |
+64 |
| Chicago |  |
+66 |
| Hawaii |  |
+80 |
| Las Vegas | |
+80 |
| Los Angeles | |
+74 |
| Maui |  |
+66 |
| Miami |  |
+92 |
| Myrtle Beach |  |
+86 |
| New York | |
+72 |
| Panama City Beach | |
+90 |
| San Diego | |
+72 |
| San Francisco | |
+60 |
| Santa Monica | |
+72 |
| Sarasota | |
+94 |
| Washington | |
+76 |
Countries:
NAME
POPULARITY
24 Hours Weather Forecast
Portsmouth
Local time: 10:36
15 sep, tuesday
| 1200 |  |
62°F | W 7 mph |
| 1500 |  |
62°F | NW 8 mph |
| 1800 | |
60°F | NW 9 mph |
| 2100 |  |
58°F | N 10 mph |
16 sep, wednesday
| 0000 | |
56°F | NE 8 mph |
| 0300 |  |
54°F | NE 9 mph |
| 0600 | |
56°F | NE 9 mph |
| 0900 | |
60°F | NE 9 mph |