Current sea water temperature:
+46.0°F
| Minimum sea water temperature in April: | 47.5°F |
| Maximum sea water temperature in April: | 39.4°F |
| Average sea water temperature in April: | 42.6°F |
| more information | |
14 days
forecast
forecast
| Portsmouth |
monthly
weather
weather
| Portsmouth |
Sea water temperature for the last 10 days:
| April 29 | 46.0°F | April 24 | 43.2°F |
| April 28 | 45.7°F | April 23 | 43.0°F |
| April 27 | 44.8°F | April 22 | 43.7°F |
| April 26 | 43.3°F | April 21 | 44.2°F |
| April 25 | 43.0°F | April 20 | 45.1°F |
Monthly sea water temperature, °F
When is the warmest sea in Portsmouth?
Based on the data about daily sea water temperature for the last three years the warmest sea in Portsmouth was noticed in August, July and September.
Monthly Sea Temperatures in Portsmouth, °F
Sea water temperature in August, °F
Show year:
2025
2024
2023
The average sea water temperature in August of 2025 was 63.3°F. The highest and lowest sea temperatures during the month were 65.3°F and 59.7°F.
Sea water temperature in July, °F
Show year:
2025
2024
2023
The average sea water temperature in July of 2025 was 63.1°F. The highest and lowest sea temperatures during the month were 67.8°F and 60.6°F.
Sea water temperature in September, °F
Show year:
2025
2024
2023
The average sea water temperature in September of 2025 was 61.1°F. The highest and lowest sea temperatures during the month were 63.3°F and 57.6°F.
current
weather
weather
| Portsmouth |
weather in
May
May
| Portsmouth |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 08:35
April 29, wednesday
0900
48°F
SW
8 mph
8 mph
1200
52°F
W
9 mph
9 mph
1500
50°F
W
6 mph
6 mph
1800
46°F
W
9 mph
9 mph
2100
45°F
W
9 mph
9 mph
April 30, thursday
0000
45°F
S
2 mph
2 mph
0300
45°F
S
2 mph
2 mph
0600
45°F
SW
2 mph
2 mph
