Anilao is a year-round diving destination — the water is warm every month and a banca boat always available — but each season has a distinct character. Choosing the right window makes the difference between 20-metre visibility and 5-metre silt, or between empty reef and resident whale shark sightings.
Peak Season: March – June
The dry northeast monsoon (Amihan) produces flat calm seas, minimal river runoff, and the year's best visibility — consistently 15–22 metres at reef sites. Water temperature rises from 27°C in March to 30°C in June. Marine life activity peaks in April and May: spawning aggregations of grouper, the highest nudibranch diversity, and regular pelagic sightings at Kirby's Rock.
Shoulder Season: November – February
Slightly cooler water (25–27°C), occasional northerly swells, and more variable visibility define the shoulder months. January and February are particularly good for muck diving — lower visibility sites like Secret Bay are largely unaffected, and the cooler temperatures bring interesting temperate-water visitors. Some exposed sites like Kirby's Rock may be diveable only on calmer days.
Wet Season: July – October
Typhoon season affects Batangas intermittently from July through October. Visibility decreases due to freshwater runoff and increased particulate suspension. However, many days during this period are perfectly diveable, and accommodation and dive packages drop significantly in price. Protected sites like Ligaya's Garden and Twin Rocks remain accessible even during southwest monsoon swell.
Best overall window: Late March to mid-May. Flat seas, peak visibility, warm water, active marine life, and no school holiday crowding.