Hobe Sound Public Beach • Statistics for September

September: The Tropics Turn The Key

September is the real turning point in the Hobe Sound surf year. Average swell height jumps back to 3ft (1.0m) and average period climbs to 8.2s, injecting real power back into the lineup. The swell direction is massively favorable: NE (31.6 percent) and ENE (30.3 percent) alone account for more than 60 percent of all waves, with a solid share of the total coming at 5ft (1.5m) or bigger - much of it from tropical cyclones and early-season extratropical lows. These long-period, east-northeasterly ground swells are exactly what this beach needs to light up. The catch remains wind quality: onshore ENE and E winds are common (14.2 percent and 14.6 percent respectively), and ideal offshore flow happens only 20 percent of the time. A passing tropical system can leave behind clean, powerful surf if the wind clocks around to the west-southwest, which is why September is often remembered as the month when hurricane swell saved the summer. Water temps are still warm at 28.8°C and air temps 27.6°C, so it's full tropical humidity and occasional heavy rain at 6.50 mm/day.