Half Moon Bay, CA
Climate overview — based on NOAA 1991-2020 normals from HALF MOON BAY, CA US.
Year-round temperatures (°F)
Climate summary
Half Moon Bay has an annual average temperature of 54.9°F with about 26 inches of precipitation per year. The warmest month is September (average high 66.4°F), and the coldest is December (average low 42.9°F). December is typically the wettest month (5.17 in) and July the driest (0.14 in).
Best time to visit Half Moon Bay
Full guide →Climate change signal
All-time records →59 of 366 (16.1%) of Half Moon Bay's all-time daily heat records have been set since 2015. If records were spread evenly across the station's history, only about 5% would fall in any given decade.
| 1930s | 7 | |
| 1940s | 36 | |
| 1950s | 56 | |
| 1960s | 45 | |
| 1970s | 30 | |
| 1980s | 32 | |
| 1990s | 34 | |
| 2000s | 50 | |
| 2010s | 55 | |
| 2020s | 21 |
Bars: number of all-time daily heat records still standing that were set in each decade.
Monthly averages
| Month | Avg High | Avg Low | Avg Temp | Precipitation | Snow | Rainy days |
|---|---|---|---|---|---|---|
| January | 59.4°F | 43.4°F | 51.4°F | 5.07 in | — | 14 |
| February | 59.5°F | 43.0°F | 51.3°F | 4.73 in | — | 14 |
| March | 60.4°F | 43.7°F | 52.1°F | 3.67 in | — | 14 |
| April | 61.0°F | 44.7°F | 52.9°F | 1.81 in | — | 9 |
| May | 61.7°F | 48.0°F | 54.9°F | 0.96 in | — | 7 |
| June | 63.9°F | 49.9°F | 56.9°F | 0.36 in | — | 5 |
| July | 64.8°F | 52.7°F | 58.8°F | 0.14 in | — | 7 |
| August | 65.6°F | 53.9°F | 59.7°F | 0.23 in | — | 8 |
| September | 66.4°F | 51.3°F | 58.8°F | 0.21 in | — | 6 |
| October | 66.4°F | 47.9°F | 57.1°F | 1.26 in | — | 8 |
| November | 62.6°F | 44.8°F | 53.7°F | 2.43 in | — | 11 |
| December | 59.0°F | 42.9°F | 50.9°F | 5.17 in | — | 13 |
Climate twins of Half Moon Bay
Why these? →The most climatically similar US cities at least 140 miles away (by monthly temperature + precipitation pattern).