Average sea water temperature in September:
+62.2°F
| Minimum sea water temperature in September: | 68.7°F |
| Maximum sea water temperature in September: | 56.5°F |
Daily 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.
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Monthly sea water temperature in Portsmouth, °F
Which USA resorts have warmest sea in September?
| Place name | September 2025 | September 2024 |
|---|---|---|
| Key West | 86.9°F | 87.4°F |
| Islamorada | 86.7°F | 87.3°F |
| Key Largo | 86.6°F | 87.1°F |
| Fort Lauderdale | 86.4°F | 86.4°F |
| West Palm Beach | 86.2°F | 86.4°F |
| Everglades | 86.2°F | 87.0°F |
| Miami Beach | 86.1°F | 86.3°F |
| Naples | 86.1°F | 87.2°F |
| Marco Island | 86.0°F | 87.2°F |
| South Padre Island | 86.0°F | 85.8°F |
| Corpus Christi | 85.8°F | 84.7°F |
| Miami | 85.8°F | 86.0°F |
| Sanibel Island | 85.7°F | 87.0°F |
| Galveston Island | 85.5°F | 84.4°F |
| Galveston | 85.5°F | 83.7°F |
| Cape Coral | 85.2°F | 86.5°F |
| Houston | 84.9°F | 83.4°F |
| Siesta Key | 84.9°F | 86.8°F |
| Sarasota | 84.8°F | 86.7°F |
| Cocoa Beach | 84.6°F | 85.2°F |
Best time for vacation in Portsmouth
Portsmouth on a weather map
Places in USA:
Name
°F
24 Hours Forecast
Portsmouth
Local time: 05:29
December 25, thursday
0600
25°F
NE
9 mph
9 mph
0900
27°F
NE
9 mph
9 mph
1200
34°F
E
9 mph
9 mph
1500
36°F
SE
12 mph
12 mph
1800
30°F
SE
17 mph
17 mph
2100
21°F
SE
15 mph
15 mph
December 26, friday
0000
16°F
SE
13 mph
13 mph
0300
12°F
SE
11 mph
11 mph
