Current sea water temperature:
+38.5°F
| Minimum sea water temperature in March: | 41.5°F |
| Maximum sea water temperature in March: | 35.4°F |
| Average sea water temperature in March: | 39.4°F |
| more information | |
14 days
forecast
forecast
| Portsmouth |
monthly
weather
weather
| Portsmouth |
Sea water temperature for the last 10 days:
| March 30 | 38.5°F | March 25 | 37.8°F |
| March 29 | 38.1°F | March 24 | 38.5°F |
| March 28 | 38.1°F | March 23 | 38.3°F |
| March 27 | 38.3°F | March 22 | 38.5°F |
| March 26 | 37.8°F | March 21 | 37.9°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
April
April
| Portsmouth |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 04:25
March 30, monday
0600
34°F
NE
12 mph
12 mph
0900
45°F
NE
13 mph
13 mph
1200
63°F
NE
14 mph
14 mph
1500
72°F
NE
14 mph
14 mph
1800
63°F
E
14 mph
14 mph
2100
55°F
NE
9 mph
9 mph
March 31, tuesday
0000
52°F
NE
6 mph
6 mph
0300
48°F
NE
5 mph
5 mph
