Andaman Sea forecast: what changed and when
The Phuket and Andaman Sea forecast for 29 September to 4 October 2025 shows a wet, windy start to the week that eases day by day. The influence of storm BUALOI and a strengthening southwest monsoon is creating rough conditions in the Andaman Sea. From 28–30 September 2025, waves in the upper Andaman will reach 2–3 meters, rising above 3 meters in thunderstorm areas.
Winds fall steadily across the period, from 26 km/h on Monday to 15 km/h by Friday and Saturday, while rain coverage drops from 70% of the area to 40%. Daytime highs climb from 31°C to 34°C, with overnight lows steady around 25–26°C.
Day-by-day summary
- 29 September (Monday) — 31°C / 26°C, heavy rain (70% area), wind 26 km/h. Sailing: strong winds, rough waters. Moderate tides.
- 30 September (Tuesday) — 32°C / 26°C, heavy rain (60% area), wind 22 km/h. Sailing: challenging for small boats, waves up to 2 m. Standard tide patterns.
- 01 October (Wednesday) — 33°C / 25°C, heavy rain (40% area), wind 19 km/h. Sailing: slightly calmer, waves 1–1.5 m. Normal fluctuations.
- 02 October (Thursday) — 33°C / 25°C, heavy rain (40% area), wind 17 km/h. Sailing: conditions improving, waves around 1 m. Regular tides.
- 03 October (Friday) — 34°C / 26°C, heavy rain (40% area), wind 15 km/h. Sailing: manageable, but caution advised. Standard tides.
- 04 October (Saturday) — 34°C / 26°C, heavy rain (40% area), wind 15 km/h. Sailing: safer for travel, waves below 1 m. Normal fluctuations.
Who and what this affects
Sea conditions of this kind matter most to open-water crossings between Phuket and the surrounding islands. Small boats and speedboats feel 2–3 metre swell long before larger vessels do, so Monday and Tuesday carry the highest chance of delays, rescheduling or cancellation. Land services are affected differently: heavy rain can slow buses, minivans and private transfers, but they generally keep running.
Operators make their own call on each departure, based on the conditions at the pier on the day. Where a sailing is cancelled for weather, the operator's own rebooking and refund conditions apply — check the terms shown with your selected ticket before you pay.
Practical tips for travellers
- Travel later in the week if your dates are flexible — Friday and Saturday show the calmest seas.
- Leave a buffer before onward flights or connections rather than booking back-to-back.
- Keep your phone reachable so the operator can contact you about changes.
- Pack rain gear and secure anything that shouldn't get wet on deck.
Check your route before you travel
Live timetables, prices and availability are shown on each route page. Compare departures from Phuket and browse the wider Thailand travel destinations to see which ferry, bus, minivan and private transfer services run on your dates.
Disclaimer: Weather, sea conditions, and tide information are subject to change. Always check local updates and forecasts before planning activities.
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