Map from Google - Sint_Maarten

The climate in Sint Maarten is tropical, hot and sunny all year round: the daily average temperature goes from 25 degrees Celsius (77 °F) in the January-March period, to 28 °C (82 °F) from June to September. The night temperature rarely drops below 20 °C (68 °F), while sometimes it can touch 35/37 °C (95/99 °F) during the day, from June to November. In the warmer months, the heat is a bit sultry, though the breezes blow and temper it a little.
Sint Maarten is an island of the Lesser Antilles, located at a latitude of 18 ° north, and is administratively divided between France and the Netherlands; the Dutch side we are dealing with here is the southern one, with Philipsburg as the capital.
Here are the average temperatures of Philipsburg.
Average temperatures - Philipsburg
Min (°C)222223232425252526252423
Max (°C)282728282930303131302928
Min (°F)727273737577777779777573
Max (°F)828182828486868888868482

Normally the rainfall is not abundant, since the annual average amounts to around 1,000 millimetres (40 inches); February and March are the least rainy months, with about 45/50 mm (1.8/2 in) of rain per month, while the rainiest period runs from August to November.
However, the rains come in the form of downpour or thunderstorm, which do not last long, so that the sun can shine throughout the year.
Here is the average precipitation.
Average precipitation - Philipsburg
Prec. (mm)755045801007085115120100115901045

In the period from June to November (but mostly from August to October), the island of Sint Maarten as in general the Caribbean, can be hit by tropical depressions and hurricanes.


In Sint Maarten, the sea is warm enough for swimming all year round, even though it is a bit warmer in the summer months, as we can see from the following table.
Sea temperature - Sint Maarten
Sint MaartenJanFebMarAprMayJunJulAugSepOctNovDec
Sea (°C)262626262728282829292827
Sea (°F)797979798182828284848281

When to go

The best time to visit the island goes from December to April, being the least muggy and outside the hurricane season, in particular the period from February to March is usually the least rainy. In May, heat and moisture increase, but the rains are not yet too abundant, and we are still out of the hurricane season. In summer, June and July are less rainy than August and September, and in these months it's also less likely for the island to be reached by tropical storms and hurricanes.

What to pack

All year round: light clothes of natural fabric, possibly a light sweatshirt and a light raincoat for thunderstorms, especially from August to November; a light sweater or sweatshirt for the evening from December to March.
For the reef, equipment for snorkeling, water shoes or rubber soled shoes.