When
Two monsoons, one island in the way, and five months when the best water is closed
The northeast monsoon from November to April is the charter season. The southwest from May to October closes three national parks by order and puts swell on the whole west coast. Phang Nga Bay works through both, and almost nobody explains why.
The short answer
When should I charter a yacht in Phuket?
November to April, with December to February as the settled core: dry air, 10 to 15 knots of northeast breeze, flat seas and 28 to 32 degrees. April is the hottest month at over 33 degrees and the month the visiting fleet starts to leave.
From May to October the southwest monsoon puts swell on the west and south of Phuket, and Mu Ko Similan, Mu Ko Surin and Mu Ko Lanta close by national park order from mid-May to mid-October. Charter is still possible in Phang Nga Bay, which lies in the wind shadow of the island, at materially lower rates and with almost empty anchorages.
7 cruising grounds, 12 months
The matrix
| Cruising ground | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Phang Nga Bay | Prime | Prime | Prime | Prime | Workable | Workable | Workable | Poor | Poor | Workable | Prime | Prime |
| Phi Phi Islands | Prime | Prime | Prime | Prime | Poor | Poor | Poor | Poor | Poor | Workable | Prime | Prime |
| Racha Islands | Prime | Prime | Prime | Prime | Workable | Poor | Poor | Poor | Poor | Workable | Prime | Prime |
| Similan and Surin | Prime | Prime | Prime | Prime | Closed | Closed | Closed | Closed | Closed | Closed | Prime | Prime |
| Krabi and Koh Lanta | Prime | Prime | Prime | Workable | Closed | Closed | Closed | Closed | Closed | Closed | Workable | Prime |
| Mergui, Myanmar | Prime | Prime | Prime | Poor | Poor | Poor | Poor | Poor | Poor | Poor | Poor | Prime |
| Gulf of Thailand | Prime | Prime | Prime | Prime | Prime | Prime | Prime | Prime | Workable | Poor | Poor | Workable |
- PrimeSettled weather, flat seas, the anchorages work. This is what people book.
- WorkableUsable with a flexible itinerary. Expect squalls, a lost afternoon or a changed anchorage.
- PoorSwell, rain and closed anchorages. Charters here are the exception rather than the season.
- ClosedClosed by national park order. Not a weather judgement, a legal one.
Closed is a legal fact, not an opinion: Mu Ko Similan, Mu Ko Surin and Mu Ko Lanta shut by national park order from mid-May to mid-October, and Maya Bay closes separately from 1 August to 30 September. An operator selling a Similan itinerary inside those dates is selling something that cannot legally happen, which makes this table the fastest reliability test in the market.
Month by month
What each month is actually like
January
The best sailing of the year, and the highest prices
Dry, 10 to 15 knots of northeast breeze, flat water and visibility at its best. Everything is open and everything is booked, and the yachts that are still free in January were free for a reason.
February
The peak, with manta season starting at Racha Noi
Conditions match January. Manta and whale shark sightings at the southern Racha pinnacles cluster from February to April, which is when the dive-led itineraries fill up.
March
Still peak, and slightly warmer
The last full month of the settled season. Temperatures climb towards the April heat, the water is at its clearest and the Similan moorings are at their busiest.
April
Hot, still fine, and the end of the visiting fleet
The hottest month of the year, over 33 degrees ashore. The northeast monsoon fades late in the month. This is when yachts that came for the season start leaving, and a late-April charter on a departing hull is the one genuine discount in the market.
May
The southwest arrives and the parks close
The monsoon turns during May and the Similan, Surin and Lanta parks close by order on the sixteenth. Phang Nga Bay stays workable in the lee of Phuket; the west and south do not.
June
Green season in the bay
Rain in heavy squalls rather than all day, empty anchorages and low-season rates. Itineraries stay east of Phuket. This is the honest bargain of the Andaman calendar for anyone who does not need the Similans.
July
Wet, but the bay still works
The same pattern as June with more of it. Phang Nga and Koh Yao continue to charter; the crossings to Phi Phi and the Rachas mostly do not.
August
The wettest stretch, and Maya Bay closes
Maya Bay closes completely from 1 August to 30 September for reef recovery. Squalls are frequent and the fleet is thin.
September
The low point of the year in Phuket
The wettest month on the island. Very few charters run, and the ones that do stay in the bay. If the dates are fixed and September is one of them, the Gulf of Thailand is the better answer than the Andaman.
October
The turn, and the parks reopen on the fifteenth
The monsoon eases through October and Mu Ko Similan and Mu Ko Surin reopen on 15 October. The second half of the month is the first window of the new season and it is not yet priced like one.
November
The season proper begins
The northeast monsoon sets in, the fleet returns from Langkawi and the Mediterranean, and the anchorages fill. Conditions are close to peak and prices have not yet reached peak.
December
Peak, with a hard premium over New Year
Excellent conditions throughout. Christmas and New Year carry a separate rate, a minimum charter length of usually seven to ten nights, and availability that is gone by the previous spring.
The green season
Where you can still sail from May to October
Phuket is a substantial island lying north to south, and Phang Nga Bay is behind it. In the southwest monsoon the island is the breakwater. The bay stays workable when the coast in front of it does not, and that single piece of geography is the whole of green-season chartering in Thailand.
The anchorage side reverses, which is the part nobody explains. In the northeast season you anchor on the east and south sides of an island. In the southwest you use the west-coast anchorages at Koh Yao, which are exposed in high season and sheltered in low. Same cruising ground, read backwards.
The rain is real and it arrives in heavy squalls of an hour or two rather than as continuous drizzle. A day can lose an afternoon. September is the wettest month on Phuket, and if the dates are fixed in September the Gulf of Thailand is the better answer than the Andaman.
Still works
Phang Nga Bay, Koh Yao, Koh Hong, the sea caves at Koh Panak
Marginal
The crossing to Phi Phi, the Racha islands
Closed by order
Similan, Surin, Koh Haa, Koh Rok, and Maya Bay in August and September
Better answer
The Gulf of Thailand, which runs January to September
Legal closures
3 routes that do not exist for part of the year
These are not weather judgements. Mu Ko Similan and Mu Ko Surin shut on 16 May and reopen on 15 October by order of the Department of National Parks, and Mu Ko Lanta closes over the same window.
The Similan and Surin islands in seven days
Closed 6 months a yearMu Ko Similan and Mu Ko Surin National Parks close by law from 16 May to 14 October. This is a legal closure, not a weather recommendation.
The far south in seven days
Closed 5 months a yearMu Ko Lanta National Park, which covers Koh Rok and Koh Haa, closes from mid-May to mid-October.
The Mergui Archipelago in ten days
Closed 8 months a yearThe practical Mergui season is December to March. Outside it the monsoon closes the archipelago and permits are not normally issued.
An operator offering one of these inside its closed window is offering something that cannot legally happen. It is the fastest reliability test available in this market, it costs you nothing to run, and it works before you have paid anybody anything.
Questions people ask about timing
- When is the best time to charter a yacht in Phuket?
- November to April, with December to February as the settled core: dry, 10 to 15 knots of northeast breeze, flat seas and 28 to 32 degrees. January and February are the best conditions of the year and the highest prices.
- Can I charter a yacht in Phuket during the monsoon?
- Yes, in Phang Nga Bay, which sits in the wind shadow of Phuket itself. What you cannot do between mid-May and mid-October is visit the Similans, the Surins, Koh Haa or Koh Rok, because those national parks are closed by order.
- When do the Similan Islands close?
- Mu Ko Similan and Mu Ko Surin close on 16 May and reopen on 15 October each year. Mu Ko Lanta, which covers Koh Haa and Koh Rok, closes over roughly the same window. Maya Bay closes separately from 1 August to 30 September.
- What is the cheapest month to charter in Phuket?
- The green season from May to October carries the lowest rates, and the second half of October is the best combination of low price and a reopened national park system. Late April sometimes produces a discount on yachts leaving Thai waters for the season.