In the 70s and 80s, a lot of surfers to Bali were perplexed by the Bali tides. No tide charts were available — I don’t believe even the Benoa harbormaster had them until later on, and then surfers in the know would do a stealth run to the harbormaster office and score a copy of the charts, which they weren’t about to share. Secret knowledge leads to uncrowded surf. Get your own, jack.
The fishermen knew the tides by heart (spring tides “air besar” and neap tides “air konda.” And if anyone reading this doesn’t know Bahasa, that “air” is not the stuff we breath (obviously) but pronounced “ayir.”)
Below is a rule of thumb for Bali tides. Most surfers know this by now, but as a public service for those who do not:
First, the moon phases are the same all over the world. You’d be surprised how many people don’t know this. They assume if it’s full moon in California, it must be half moon in Bali. Seriously. Over the years, I’ve had telexes and then faxes and then emails from overseas friends planning surf trips asking me about moon phases in Bali.
Second, full and new moons are marked on Balinese calendars. They are available pretty much everywhere. But if you’re online, moon phases are available at many sites, such as this one. The DATES of the new and full moon phases for each month can be found here.
Third, the biggest tides occur approximately one to two days *after* the new and full moons, and are fullest around midday. This means low tides, with exposed reefs, are early morning (with incoming tide) and late afternoon (on the outgoing). Unfortunately, this rule of thumb doesn’t give you the absolute height of a tide — a 2.1 tide is quite different than a 2.5, the latter often throwing up unmanageable currents, and on big swells washing away warungs and beach shacks.
Fourth, neap tides occur on mid-moons (first quarter and last quarter, with high-ish tides in the am and pm, and the lower tides mid-day, but these tide changes are minor, I believe most reefs are usually covered and paddle-out-able almost all day without the reef dance walk.
Some other informal moon information, gathered from countless nights on decks of boats:
Full moon rises around sunset and sets around dawn.
New moon (mostly invisible) rises around dawn and sets around sunset (which is when we commonly see the new moon sickle).
If you look up at the night sky at a partial moon, with the top portion illuminated, it is waxing toward full. If the bottom part is illuminated, it is waning toward new. (Oh boy, do I have that the right way around? I think so. I better get back on a boat deck soon…with surf).