The Best Months for Pig Island
The best time for Pig Island from Koh Samui: February to April are driest, November is wettest and January is not dry. Rain by month (Thai Meteorological Department).
February to April are the driest months on Koh Samui and November is the wettest. The Thai Meteorological Department’s 1991-2020 normals for its Ko Samui station put February at 64.3 mm of rain on 5.6 rainy days and November at 444.6 mm on 18.7 days; October and December are wet too. January is not a dry month: 126.8 mm on 11.1 rainy days. The dates Samui Jetski Safari’s Koh Samui: Jetski Safari, Snorkeling to Pig & Virgin Islands runs are in the calendar below, from $203 per jet ski for one or two riders (checked November 2026).
The calendar above is the jet ski safari, with 861 reviews (checked November 2026). It shows only the dates it runs.
The short answer
If you can choose, go between February and April, when the station records the fewest rainy days of the year. From May to September it rains on about half the days of each month, with monthly totals well below those at the end of the year. October to December, and November above all, are the months with the most rain, so plan spare days into a stay then. Wherever your dates fall, book a trip with a weather refund and keep a second day free.
Rain by month at the Ko Samui station
| Month | Rain (mm) | Rainy days |
|---|---|---|
| January | 126.8 | 11.1 |
| February | 64.3 | 5.6 |
| March | 115.8 | 5.9 |
| April | 82.9 | 8.1 |
| May | 131.6 | 14.0 |
| June | 133.6 | 13.1 |
| July | 117.0 | 14.3 |
| August | 102.2 | 14.5 |
| September | 117.5 | 15.0 |
| October | 294.9 | 19.3 |
| November | 444.6 | 18.7 |
| December | 263.1 | 14.2 |
| Year | 1,994.3 | 153.8 |
Mean monthly rainfall and mean number of rainy days, 1991-2020, Ko Samui station (Thai Meteorological Department, Climatological Data for the Period 1991-2020, checked November 2026). The station records the island as a whole, not Koh Madsum itself.
March shows what a monthly total can hide: 115.8 mm, but on only 5.9 days, so its rain falls on few days of the month. The rainy-day column is the better guide to your chances of a dry day on the water.
What bad weather does to a booking
On the jet ski safari, if the company cancels for weather before the tour starts, you get a full refund or a new date; if bad weather starts during the ride, the route can be shortened, a stop skipped or the tour ended early, and then there is no refund. Free cancellation runs up to 24 hours before. Happy Samui's speedboat half day normally runs in light rain and ordinary tropical weather, and changes the plan or the date when conditions are severe. TripGuru Thailand's island-hopping day offers a full refund or a new date in bad weather, and warns that snorkelling visibility is often low from December to March. Snorkelling at Koh Tan depends on the sea, and on some trips a rough day means more time on Pig Island instead.
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Pig Island and Ang Thong
None of the Pig Island trips carded here combines Koh Madsum with Ang Thong Marine Park; a day in Ang Thong is a separate booking. angthongtourreviews.com covers the Ang Thong day trips in depth.
More from Koh Samui
Samui Trips with Open Dates
Other trips from Koh Samui with live availability. What each includes is on its listing.
Pick Your Day for the Jet Ski Safari
2.5 hours on a jet ski for one or two, Koh Tan snorkelling and Koh Madsum, with a full refund or a new date if the company cancels for weather before the start.
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