Current Sea Water Temperature:
+53.6°F
| Maximum Sea Water Temperature in October: | 64.6°F |
| Minimum Sea Water Temperature in October: | 53.2°F |
| Average water temperature in October: | 58.1°F |
| detailed information | |
Sea Water Temperature for the Last 10 Days:
| October 26 | 53.6°F | October 21 | 55.2°F |
| October 25 | 53.8°F | October 20 | 55.0°F |
| October 24 | 54.2°F | October 19 | 55.0°F |
| October 23 | 54.0°F | October 18 | 56.4°F |
| October 22 | 55.4°F | October 17 | 59.0°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 65.3°F. The maximum and minimum values were 60.6°F and 69.2°F respectively.
USA Resorts:
NAME
F°
| Boston |  |
+58 |
| Chicago | |
+58 |
| Hawaii | |
+80 |
| Houston |  |
+74 |
| Las Vegas |  |
+64 |
| Los Angeles | |
+74 |
| Maui | |
+72 |
| Miami | |
+82 |
| New York | |
+62 |
| Panama City Beach | |
+64 |
| San Diego | |
+74 |
| San Francisco | |
+60 |
| Santa Monica | |
+72 |
| Tampa | |
+72 |
| Washington | |
+58 |
Countries:
NAME
POPULARITY
24 Hours Weather Forecast
Portsmouth
Local time: 00:49
27 oct, tuesday
| 0300 |  |
46°F | S 9 mph |
| 0600 | |
42°F | S 11 mph |
| 0900 | |
44°F | S 10 mph |
| 1200 |  |
48°F | W 4 mph |
| 1500 | |
50°F | NW 7 mph |
| 1800 |  |
44°F | N 8 mph |
| 2100 | |
42°F | E 5 mph |
28 oct, wednesday
| 0000 | |
38°F | SE 6 mph |