Hoi An, Central Vietnam 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 05:00 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/Ho Chi Minh local. Folk tradition, not a scientific forecast.

Hoi An sits on the Thu Bon River estuary in Quảng Nam province, the ancient merchant quarter a few minutes' walk from the water. The South China Sea is 3 km east at Cua Dai Beach; the tidal signal travels that entire distance up the river channel and shapes almost every water-based activity in town. The tidal pattern here is mixed semidiurnal with a pronounced diurnal inequality — in practice that means two highs and two lows per day, but one high is noticeably taller than the other. Mean spring range at the Thu Bon mouth is 0.5–1.0 m, unusually small for the South China Sea. The shallow continental shelf geometry at this latitude compresses the tidal amplitude; what you lose in range you feel in current. The flood tide pushes into the river mouth from roughly 0800 to 1400 local time on a typical day, and the ebb drains back through the late afternoon and evening. The timing shifts by 45–50 minutes each day, so checking the day's specific table matters. For anglers and boat handlers, the current direction in the Thu Bon channel is the number that counts. At flood, upwelling from the sea pushes nutrients into the lower estuary and concentrates fish near the bends between the Ancient Town and Cua Dai. Local fishermen using hand lines and nets from small motorised skiffs time their sets to the last hour of flood and the first hour of ebb — the transition period when baitfish school near the surface. The traditional thuyền thúng, round coracle-style basket boats woven from bamboo and sealed with pitch, launch from the villages between the Ancient Town and the beach. Their low draft means they handle any tide state, but returns to shore go with the ebb when the work is done. Cua Dai Beach is the direct coastal face of the estuary. The beach has lost more than 100 m of width since 2010 — upstream dams on the Thu Bon River system cut off the sand supply that historically replenished the shore. At high tide the water now reaches the base of the remaining seawall and the beach can all but disappear. At low tide, a 40–60 m strip of wet sand exposes, wide enough for swimming and walking but not the broad beach the town was known for a decade ago. Photography of the remaining beach is better timed to the two hours around low water, when the sand is exposed and the light on the dune remnants is clean. Sunrise shoots work well from the beach — face east toward open water. An Bang Beach, 3 km north of Cua Dai along the coast road, is slightly more sheltered and loses less width at high water because it sits in a minor embayment. Families with young children often prefer it for that reason — the depth gradient is gentler and the beach width more consistent across the tidal cycle. The Cham Islands — Cù Lao Chàm — lie 18 km offshore as part of a UNESCO Biosphere Reserve. Speedboats make the crossing in 20 minutes from Cua Dai pier; wooden tourist boats take 45 minutes. Departure times are set around the morning flood tide window, typically 0800–0830, which gives calmer conditions outbound. The anchor grounds and snorkel sites around the islands have depths of 3–8 m, and low tide exposes coral heads that are navigable for wooden boats but require care from anything drawing more than a metre. Return departures from the islands cluster around 1200–1300 before the afternoon ebb strengthens and the chop builds on the crossing. The monthly Lantern Festival — held on the 14th night of each lunar month when the moon is full — turns the Ancient Town electric-light-free after dark. Paper lanterns floated on the Thu Bon River drift with whatever the tidal current is doing at the time. In the flood window the lanterns move upriver, inland, past the old warehouses and away from the Japanese Covered Bridge. On the ebb they reverse toward the sea. The direction is uncontrolled and adds to the spectacle — check whether the festival night falls in a flood or ebb window if you want to photograph lanterns drifting in a specific direction. The Japanese Covered Bridge at the western edge of the Ancient Town is the symbolic centre of Hoi An and sits right on the river bank. At the highest tides of the spring cycle, river levels at the bridge rise noticeably — not dangerously, but the stone steps at the riverbank access points go underwater. This is worth knowing for photographers setting up low-angle shots of the bridge reflected in the water. Tide data for Hoi An, Central Vietnam comes from the Open-Meteo Marine API, a gridded model product. Timing accuracy is ±45 minutes, height accuracy ±0.3 m — usable for trip planning, not for navigation.