Vejret i Nusa Penida (Penida) i september

Regulars are specific this counts as high season for the nearby islands, accommodation booked out and choice genuinely limited, sea conditions themselves settling down by around the second week of the month after an unpredictable stretch through August and early September. Our row backs that mild, genuinely wet read, 25.8C reading as a hot 30C, over 21.5C nights feeling 25C, with a substantial 89.6mm of rain across 15.5 days and humidity at 87 percent. Regulars are consistent this remains a genuinely good month for diving despite the crowds, water temperature at depth capable of dropping below 20C even while the surface stays considerably warmer. The sea sits at a warm 26.2C. The record: 11 hours of sun, a 14.6 kph wind and AQI 43.

June is generally good for the sea state here and the dry season's visibility is what the divers come for - but regulars add that June to September are the windy months, that nobody can promise a calm strait, and that the morning boats are reliably the kindest. Take the earliest departure; the crossing is only half an hour. Our row is a reminder that dry season is a local term: 80.4mm across 16.6 days at 88 percent humidity, so rain touches most days even now, just briefly. Heat is moderate by Indonesian standards at 26.1C, though it reads as 30C, over 22.1C nights and a 27.5C sea. The record: 10.6 hours of sun, a 14 kph wind and AQI 40.

July is dry season and the crossing is usually flatter for it, but this is also the month regulars warn about wind: July winds have made the strait choppy enough to cancel the fast boats for days at a stretch. Their advice is the earliest departure, because mornings are calmer. The same logic applies once you are across - operators decide on the morning whether Manta Bay is on, since it faces the exposed south and gets both the chop and the strong currents, and on a bad day the boats run to Gamat Bay instead. Penida as a day trip out of Sanur is a 10 to 12 hour day, and the early ferry is also how you get ahead of the crowd. The record: 25.1C days that feel like 28C, 21.2C nights, 14.7 precipitation days carrying 71.9mm, humidity 87 percent and a 26.9C sea.

Forum posters are direct that February sits at the prime, not the tail end, of Bali's wet season - hot, very humid, with downpours a real daily possibility and sunsets a genuine hit or miss. Posters do note Nusa Penida itself tends to run somewhat drier than mainland Bali at the same time of year, though still squarely within the wet season overall. The bigger practical concern posters raise isn't the rain itself but sea state: crossings and water activities depend on cooperating conditions, and the strait can turn genuinely choppy and unpredictable this time of year, sometimes disrupting ferry schedules and boat trips more than the rain does. Water temperatures for diving are reported around 28C with occasional cooler upwells to around 25.5C.

Nusa Penida's forum places August in the middle of the dry season, low humidity and probably one of the best windows weather-wise. Regulars flag the Bali-Lombok strait's wind as the real factor to watch here specifically — when it picks up, boat crossings and dive conditions can turn choppy — and recommend a jacket or shawl for cooler nights in the island's hillier spots.