Surface water temperature

Surface water temperatures have a strong north to south gradient, and a small annual cycle, being lowest around March 15, and highest around September 15. The average surface water temperature around O'ahu is 24 C (75 F) in winter and 27 C (81 F) in summer. The variations of temperature tend to parallel the island chain, i.e. surface waters are in general warmer to the west at a given latitude.

WINTER - SPRING

SUMMER - FALL
Average surface water temperatures for February to April ("winter", the coldest period), May to July ("spring"), August to October ("summer", the warmest period), and November to January ("fall"). Period: 1987 to 1991. Source: AVHRR weekly Multichannel Sea-Surface Temperature (MCSST) Project, Jet Propulsion Laboratory, NASA. Units: degrees Celsius.