Average sea water temperature in January:
+41.6°F
| Minimum sea water temperature in January: | 45.9°F |
| Maximum sea water temperature in January: | 37.8°F |
Daily sea water temperature in January, °F
Show year:
2026
2025
2024
The average sea water temperature in January of 2026 was 40.9°F. The highest and lowest sea temperatures during the month were 42.3°F and 37.8°F.
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Monthly sea water temperature in Portsmouth, °F
Which USA resorts have warmest sea in January?
| Place name | January 2026 | January 2025 |
|---|---|---|
| Kailua Kona | 78.3°F | 78.2°F |
| Honolulu | 77.2°F | 77.6°F |
| Hawaii | 77.2°F | 77.5°F |
| Kahului | 77.2°F | 77.1°F |
| Maui | 77.0°F | 76.9°F |
| Kauai | 77.0°F | 75.0°F |
| West Palm Beach | 76.6°F | 75.5°F |
| Oahu | 76.1°F | 76.5°F |
| Fort Lauderdale | 75.9°F | 75.1°F |
| Miami Beach | 74.0°F | 73.1°F |
| Key West | 72.5°F | 70.3°F |
| Key Largo | 71.7°F | 71.1°F |
| Miami | 71.2°F | 70.7°F |
| Everglades | 70.8°F | 68.6°F |
| Marco Island | 68.2°F | 65.2°F |
| Naples | 67.7°F | 64.7°F |
| Cape Coral | 67.3°F | 64.3°F |
| Cocoa Beach | 66.9°F | 60.9°F |
| Siesta Key | 65.0°F | 61.5°F |
| Sarasota | 65.0°F | 61.2°F |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 09:42
April 29, wednesday
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
0900
46°F
W
4 mph
4 mph
