Half Moon Bay Weather in September

With daytime temperatures of 22°C (72°F) and nighttime lows of 11°C (52°F), September in Half Moon Bay brings high temperatures during the day. The excellent weather makes it an appealing time to visit.

Rainfall in Half Moon Bay in September

Typically around 3 days of rainfall are expected, averaging 5.6 mm (0.2 in) for the month. Rain is scarce this month and when it does fall, it tends to be light. Unlikely to disrupt plans significantly.

Temperature in Half Moon Bay in September

September in Half Moon Bay is generally excellent, with days reaching 22°C (72°F) and nights settling around 11°C (52°F). This gives the month a fairly typical daily rhythm, with warmer afternoons and more comfortable nights. At 11°C (52°F) overnight, it can feel quite a bit cooler after dark. Worth packing something warmer for evenings, but the cooler temperatures are ideal for sleeping. On average, it has the peak temperatures of the year.

Sunshine in Half Moon Bay in September

There are approximately 270 hours of sunshine this month, resulting in mostly clear days.

Wind Speed in Half Moon Bay in September

Wind speeds average 5 m/s (10 knots) during September. At this speed, gentle to moderate breezes make small trees sway and the wind creates whitecaps on water bodies. Daily variations range from moderate winds to stronger breezes, creating excellent conditions for sailing, kite flying and wind sports.

Average water temperature in September

The water is 14°C (57°F) this month, cool enough to feel refreshing on a warm day, but cold enough that most people won't stay in for long without a wetsuit.

Our weather planner can help you find worldwide destinations with pleasant weather during this period. May, June, July, August, September and October typically offer the best weather for Half Moon Bay.