Het weer in Kralendijk (Bonaire) in september

Forum posters describe September as genuinely the hottest month of the year here, with less wind than usual making the heat feel more intense - the sun feels noticeably stronger on a still, windless day even for experienced divers and snorkelers. Posters are consistent that Bonaire's rainy season more typically runs October through January, so September itself usually sees comparatively little rain, generally in the form of brief, intense showers that don't meaningfully disrupt diving or snorkeling. Posters note the island stays noticeably quieter in September, with fewer tourists and some restaurants closed for a slower stretch, though Bonaire doesn't see the mass seasonal closures some other Caribbean islands in the hurricane belt experience. Posters generally recommend sun protection given how intense the exposure feels without a cooling breeze.

Regulars are specific this island stays genuinely windy nearly all the time, locally known as the westerlies, though snorkeling remains nice in spots that get some natural buffer from the breeze. Our row backs that hot, genuinely wet read, 31.7C reading as a scorching 35C, over 27.1C nights feeling 28C, with 45.2mm of rain across 9.8 days and a real 35.8 kph wind. Regulars are consistent this counts as shoulder or off season, weather-wise barely distinguishable from May, one visitor's mid-June two-week stay specifically reporting favorable conditions and noticeably thinner crowds. The sea sits at a bath-warm 28.2C. The record: 11.3 hours of sun, humidity 81 percent and AQI 56.

May sits inside this island's windier stretch, roughly January through August, and our column carries it at a genuinely high 35.6 kph. Regulars explain why that barely troubles most visitors: the trade winds blow steadily from the east, leaving the leeward west side - where nearly all the diving and snorkeling happens - predictably calm, while the exposed south sites like Margate see more surge on a strong-wind day. Air is 31.3C reading as 35C at 81.4 percent humidity, over 27C nights, with 21.5mm of rain across 5.2 days. The sea is 27.4C. One regular names May and early June as their favourite non-winter stretch specifically because of this wind-shadow effect. The record: 11.2 hours of sun and AQI 57.

On Bonaire the rainy season and the high season are the same months, which sounds like a problem and is not. Regulars describe January days in the mid-eighties Fahrenheit and usually sunny, with rain arriving as a hard, short shower - thirty minutes counts as a long one here, and a whole wet day is the exception. Our 10.4 precipitation days spread just 32.3mm between them, three millimetres each, which is that described in figures. The wind runs January to August at 15 to 20 mph, our row's 33.7 kph, and it keeps the insects down while the dive and snorkel sites stay sheltered on the lee shore. Busier now, but only by this island's standards. The record: 29.9C over 24.8C, a 26.9C sea and AQI 48.

Our row gives Bonaire 33.3 kph in April, among the windiest figures anywhere here, and regulars explain why it barely matters: the wind blows almost constantly - which is what makes this a windsurfing island - but practically every dive and snorkel site sits on the lee shore, so the same wind is offshore there and the water stays flat. December to May is when the trades help settle the sea, so April is inside the good window. A strong easterly does put surge on the southern sites like Margate and Red Beryl, and the calmer entries are then nearer town. Shore diving is the island's draw, with a warning attached: getting in and out over the rock in gear is the hazardous part. The record: 30.9C over 26.2C, 17mm across 3.9 days, a 26.8C sea and AQI 54.