Swimming in Half Moon Bay in september 2025: Average sea temperature in september and tide times in september 2025
Average sea temperature in Half Moon Bay in september 2025.
In september, according to seasonal norms, the sea temperature in Half Moon Bay is:
Minimum: 56°F
Average: 58°F
Maximum: 59°F
Other useful seasonal weather averages in september:
- Outside temperature: 61°F to 69°F
- Most common weather: "Clear/Sunny"
- The wind blows at 9.9mph
- It rains a total of 0.3in, over 0 day(s).
Should we swim in Half Moon Bay in september?
No... The water temperature in Half Moon Bay in september is freezing
You won't be able to swim in Half Moon Bay in september! The water temperature is freezing, reaching as low as 56°F (and only 59°F at best)! Our advice: if you are going to Half Moon Bay this month, plan to sightsee and forget the beach!
Note also that in september, the climate is perfect with an average outside temperature of 65°F, 0.3in of precipitation (over 0 days) and 82.53 % humidity.
Water and normal seasonal temperatures in Half Moon Bay in september
| September | |||
| Average sea temperature | 58°F | ||
| Minimum sea temperature | 56°F | ||
| Maximum sea temperature | 59°F | ||
| Average outside temperature | 65°F | ||
| Maximum outside temperature | 70°F | ||
| Minimum outside temperature | 61°F | ||
| Wind speed | 11.8mph | ||
| Wind temperature | 61°F | ||
| Precipitation | 0.3in | ||
| Number of days of rain | 0 jour(s) (1%) | ||
| Humidity | 83% | ||
| Visibility in kilometers | 9.69km | ||
| Cloud cover | 15% | ||
| Our opinion | freezing swimming |
Chart of the tides in september 2025
Tide times in september 2025 in Half Moon Bay
Swim elsewhere in California in september
| City | Average T° | Min. T° | Max. T° | Our opinion | Los Angeles in september | 67°F | 70°F | cool swimming | San Francisco in september | 58°F | 59°F | freezing swimming | San Diego in september | 67°F | 70°F | cool swimming | Big Sur in september | 58°F | 60°F | freezing swimming | Carmel-by-the-Sea in september | 59°F | 61°F | freezing swimming | Eureka in september | 53°F | 57°F | freezing swimming | Hollywood in september | 67°F | 70°F | cool swimming | Malibu in september | 66°F | 69°F | cool swimming | Mendocino in september | 55°F | 57°F | freezing swimming | Morro Bay in september | 59°F | 62°F | freezing swimming | Oakland in september | 58°F | 59°F | freezing swimming | Pismo Beach in september | 59°F | 62°F | freezing swimming | San Clemente in september | 68°F | 70°F | cool swimming | Santa Barbara in september | 62°F | 65°F | cold swimming | Santa Cruz California in september | 58°F | 60°F | freezing swimming | Santa Monica in september | 67°F | 70°F | cool swimming | Ventura in september | 64°F | 67°F | cool swimming | Bodega Bay in september | 56°F | 58°F | freezing swimming | Carlsbad in september | 68°F | 70°F | cool swimming | Huntington Beach in september | 67°F | 70°F | cool swimming |