Windang Island • Statistics for September

September: Spring Swell Mix

September is the spring transition. Ideal wind remains solid at 35%, the average period is 9.0s and height holds at around 5-6ft (1.6m). The swell rose is a true mix: SSE still dominates at 17%, true S drops to 16%, SE adds 11%, and NE/ENE blocks have risen to around 20% combined. E/ESE also adds another 16%. This broadening of direction means more inconsistent periods, but it also creates variety. The dominant wave heights are still in the 3-6.5ft (1-2m) range, with around 10% of the wave distribution reaching 6.5ft (2m) or more. The wind distribution starts to shift away from the hard winter westerly: NNW is the leader at 15.3%, W is 9.9%, WSW 7.9%, while E/SE onshore flows are still limited. Good surf is often found in the wake of cold fronts and during high-pressure ridges, when NW offshores hold the surface together. Water temperature is 17.7°C, air temperatures average 12.8°C (min 1.8°C, max 31.8°C), and rainfall is low at 1.83 mm/day.