Average sea water temperature in December:
+45.8°F
| Minimum sea water temperature in December: | 50.7°F |
| Maximum sea water temperature in December: | 41.9°F |
Daily sea water temperature in December, °F
Show year:
2025
2024
2023
The average sea water temperature in December of 2025 was 45.4°F. The highest and lowest sea temperatures during the month were 47.8°F and 43.5°F.
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Monthly sea water temperature in Portsmouth, °F
Which USA resorts have warmest sea in December?
| Place name | December 2025 | December 2024 |
|---|---|---|
| Kailua Kona | 79.4°F | 78.3°F |
| West Palm Beach | 79.2°F | 78.4°F |
| Fort Lauderdale | 78.9°F | 77.6°F |
| Honolulu | 78.7°F | 78.3°F |
| Hawaii | 78.6°F | 78.3°F |
| Kauai | 78.4°F | 76.0°F |
| Maui | 78.2°F | 77.8°F |
| Miami Beach | 77.8°F | 75.9°F |
| Oahu | 77.2°F | 77.2°F |
| Islamorada | 77.0°F | 73.4°F |
| Key Largo | 76.8°F | 73.1°F |
| Key West | 76.4°F | 72.6°F |
| Miami | 76.1°F | 73.0°F |
| Everglades | 74.2°F | 69.7°F |
| Marco Island | 72.1°F | 68.0°F |
| Naples | 71.7°F | 67.7°F |
| Cape Coral | 71.5°F | 67.8°F |
| South Padre Island | 71.4°F | 71.9°F |
| Sanibel Island | 71.1°F | 67.1°F |
| Siesta Key | 69.5°F | 65.6°F |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 01:29
December 25, thursday
0300
23°F
E
6 mph
6 mph
0600
25°F
NE
9 mph
9 mph
0900
28°F
E
7 mph
7 mph
1200
32°F
E
10 mph
10 mph
1500
36°F
SE
13 mph
13 mph
1800
28°F
SE
17 mph
17 mph
2100
21°F
SE
15 mph
15 mph
December 26, friday
0000
16°F
SE
12 mph
12 mph
