Sisters' Islands Marine Park tide times

Predictions: Open-Meteo Marine (MeteoFrance SMOC, 0.08° grid) — heights relative to MSL (not chart datum / LAT). Model-derived.

Model-derived from a global ocean grid. Useful indication; expect about ±45 minutes on average vs. a local harmonic gauge, individual stations vary widely. See /methodology for per-region detail. Not for navigation.

Conditions as of 12:00 local time. Refreshes daily.

Predictions: Open-Meteo Marine (MeteoFrance SMOC, 0.08° grid) — heights relative to MSL (not chart datum / LAT). Model-derived. · Not for navigation.

The angler tradition for major/minor fishing windows: major ≈3-hour windows around moon transit and opposition; minor ≈2-hour windows around moonrise and moonset. Times are Asia/Singapore local. Folk tradition, not a scientific forecast.

Last spring tide on Tue 19 May (range 2.7m). Next neap on Fri 22 May.

Spring tides cluster around new and full moons (biggest swings). Neap tides land on quarter moons (smallest swings). See the spring tide and neap tide glossary entries for the why.

Sisters' Islands Marine Park comprises two small islands — Big Sister (Pulau Subar Laut) and Little Sister (Pulau Subar Darat) — and the surrounding reef and inter-tidal zone approximately 6 kilometres south of the Singapore mainland. The park was gazetted in 2014, making it Singapore's only designated marine park, and it protects a stretch of coral reef, inter-tidal reef flat, and seagrass beds that represent some of the best-preserved inshore marine habitat remaining in Singapore waters. The tidal character of the Sisters' Islands is central to their ecological value. The spring tidal range in the Strait of Singapore is approximately 2.7 metres, and the mixed semidiurnal regime with its pronounced diurnal inequality creates the twice-monthly low water springs when the reef flat drops to within 0.1 metres of chart datum. At these low waters, the inter-tidal reef flat between and around the two islands is exposed for 2 to 3 hours, and this window is when the marine park's guided reef walks take place. The Marine Conservation Group runs monthly reef walks at low water springs, with advance registration required through their website. Participants wade the flat in groups of 20, guided by trained volunteers, and see intertidal organisms — knobbly sea stars, sea cucumbers, carpet anemones, decorator crabs, nerite snails, and inter-tidal fish including mudskippers and blennies — that are invisible at high water. The reef flat between the two islands drains first, followed by the deeper reef slope on the outer (southern) face, which faces the Strait of Singapore. Water on the outer slope is cleaner, with visibility of 3 to 6 metres on good days — the incoming tide brings clearer water from the Strait. The outer slope drops to 8 to 12 metres on a gentle gradient before reaching the sandy channel bottom. Grouper, wrasse, and parrotfish are present on the reef; the fish community has recovered since the area's protection, with reef fish counts showing a positive trend since 2014. Coral restoration is a central part of the park's management programme. Nursery frames — horizontal structures resembling small tables — are anchored in 3 to 5 metres of water inside the protected zone. Fragments of live coral, primarily Acropora and Pocillopora species, are attached to the frames and grown out before transplantation to damaged reef sections. The frames are visible from the surface on clear days. Two restoration programmes operate concurrently: one led by the National University of Singapore's Reef Ecology Lab, and one by the Marine Conservation Group in partnership with the National Parks Board. Access is by scheduled ferry from Marina South Pier — not all services stop at Sisters' Islands; check the current schedule. The ferry landing is on Little Sister (Pulau Subar Darat), the smaller of the two islands. Big Sister has no permanent landing facilities but is accessible by wading from Little Sister at low water when the connecting reef flat is exposed. Both islands have small beaches but limited facilities — visitors should be self-sufficient with food and water. The park is a no-fishing zone. All marine life is protected within the gazetted boundaries, and anchoring on the reef is prohibited. Boats must use the designated mooring buoys on the northern side of the islands. Snorkelling outside the guided walk programme is permitted, but scuba diving requires a permit from the National Parks Board. Predictions on this page come from Open-Meteo Marine, a gridded global ocean model. Accuracy is typically within plus or minus 45 minutes on timing and 0.2 to 0.3 metres on height — model-derived, not from a local gauge. The local tide authority is the Maritime and Port Authority of Singapore (MPA), which publishes annual tide tables for Singapore Strait reference stations.