Current sea water temperature:
+64.6°F
| Minimum sea water temperature in July: | 70.3°F |
| Maximum sea water temperature in July: | 57.0°F |
| Average sea water temperature in July: | 63.6°F |
| more information | |
14 days
forecast
forecast
| Portsmouth |
monthly
weather
weather
| Portsmouth |
Sea water temperature for the last 10 days:
| July 21 | 64.6°F | July 16 | 65.8°F |
| July 20 | 65.7°F | July 15 | 67.6°F |
| July 19 | 66.4°F | July 14 | 66.0°F |
| July 18 | 64.9°F | July 13 | 64.6°F |
| July 17 | 64.8°F | July 12 | 64.8°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:
2026
2025
2024
The average sea water temperature in July of 2026 was 65.8°F. The highest and lowest sea temperatures during the month were 70.2°F and 63.0°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
July
July
| Portsmouth |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 11:53
July 21, tuesday
1200
84°F
NW
12 mph
12 mph
1500
84°F
NW
13 mph
13 mph
1800
79°F
NW
12 mph
12 mph
2100
64°F
NW
9 mph
9 mph
July 22, wednesday
0000
66°F
N
10 mph
10 mph
0300
68°F
NE
9 mph
9 mph
0600
66°F
NE
9 mph
9 mph
0900
70°F
NE
9 mph
9 mph
