Water temperatures range from the low 70s F (about 22 Celsius) in January and February, to the low 80s F (about 30C) in August and September. A full 2mm wet suit is likely to be adequate for most people. In summer, I am comfortable in a T-shirt.

There is an overall westerly movement of water around the Hawaiian islands. This is modified locally, particularly by tidal currents. The difference between high and low tide is approximately 2 feet (0.6m). Tidal currents can sometimes move faster than people can swim, so it is a good idea to consult tide tables before diving.

If you are planning on doing a lot of shore diving, it is also worth noting that in winter, it is quite common to have long periods of high surf, particularly on the north and west shores, which make shore diving entries and exits more difficult, and sometimes impossible.

Glenn James weather report and sea conditions for divers.
Marine Forecast 877-3477
Maui Recreational Forecast 871-5054 & 877-5111

Average Temperatures

(After 'Exploring Tropical Isles and Seas' by Frederic Martini)

	Air Temp C (F)	Sea Temp C (F)	Wind Dir	Swell Dir
Jan	21.7 (71)	22.8 (73)	NE	NE
Feb	21.7 (71)	22.8 (73)	NE	NE
Mar	22.2 (72)	23.3 (73.9)	ENE	NE
Apr	22.8 (73)	24 (75.2)	ENE	NE
May	23.9 (75)	25.2 (77.4)	ENE	-
Jun	25 (77)	26.4 (79.5)	ENE	-
Jul	25.6 (78)	26.4 (79.5)	E	SW
Aug	25.6 (78)	26.8 (80.2)	E	SW
Sep	25.6 (78)	26.7 (80.1)	ENE	-
Oct	25 (77)	26.3 (79.3)	ENE	-
Nov	23.9 (75)	24.9 (76.8)	ENE	-
Dec	22.8 (73)	23.2 (73.8)	ENE	NE