Pogoda Kagoshima — wrzesień

Yakushima-forum threads on rain discuss this island's reputation as one of Japan's genuinely wetter destinations, September overlapping with typhoon season and capable of bringing real disruption to travel plans and ferry schedules. Posters describe conditions as still warm, summer-like temperatures lingering through the month, comfortable enough for light clothing even as the rain risk climbs. Regulars are consistent when it rains here it tends to come down hard rather than as a gentle drizzle, proper gear genuinely essential for any trek toward the Jomon Cedar or Shiratani Unsui Gorge. Posters call September still a workable trekking month despite the risk, slightly calmer temperatures than peak summer making the walk more comfortable. Regulars recommend building real flexibility into any itinerary given how disruptive a typhoon can be to onward travel. The record: 22.4C days feeling like 24C, 20.5C nights, an extraordinarily high 246mm across over 18 days and 80 percent humidity.

This is one of the earliest places in Japan to enter the rainy season, and regulars date it precisely - the meteorological agency has called it for southern Kyushu as early as May 11 in some years, typically late May into early June, running to about mid-July. It does not rain every day, and when it does it is rarely the tropical squall people picture; the real humidity does not bite until July. Our row already shows the shift: 263.9mm across 12.9 days, well ahead of April, at 81.1 percent humidity, though the temperature stays comfortable at 25.6C reading as 27C over 17.5C nights. Sakurajima keeps smoking through all of it regardless of the season - locals here carry a dedicated ash umbrella rather than count on a rain one. The sea is 21C. The record: 7.9 hours of sun, a 14.9 kph wind and AQI 59.

Kyushu opens the blossom season and Kagoshima is among the warm places where early trees show in late March - but the board is careful about two things. Peak lasts three to five days, and it lands somewhere in the last week of March or the first of April rather than on a date you can book, so the year's forecast is the only planning tool. And late March weather here is changeable and often wet. Our row agrees emphatically: 168.3mm across 12.3 days with only 7.6 hours of sun, under 18.5C days and 9.4C nights that feel like 7C in a 16.3 kph wind. The volcano across the bay adds ash to the city whenever the wind sets that way. The record: humidity 77 percent, a 17.9C sea and AQI 54.

Regulars say you will not find snow in Kyushu in early December and that the cities are cold without being subzero - our row's 15.3C day over a 6.7C night reading as 4C is exactly that, and the 0.1cm in the snow column belongs to the hills rather than the streets. What makes Kagoshima different from any other winter city here is in the air rather than the forecast. Sakurajima sits across the bay and sheds ash even when it is not properly erupting, enough to collect on the pavements; residents live with it as routine. Our AQI of 52 measures pollution, not ash, so the column understates what you will actually notice. The record: 68.1mm across 7 precipitation days, humidity 75 percent, 7 hours of sun and a 19.1C sea.

Mid to late November is autumn-colour season in Kyushu, and the forum's rule is altitude before date: the turn starts above about 1,000m in late October and works down to the plains by late November into early December. In practice that makes Kirishima the November drive, its great torii framed by red and gold, while Sengan-en on the bay is the in-town garden, at its best in mid-autumn with chrysanthemum displays through the month. November has a reputation as one of Japan's driest months; our own row is the caution, because Kagoshima is not where that holds - 111.7mm over 8.6 precipitation days and only 7.6 hours of sun a day. The rest: 21.2C days, 12.7C nights, humidity 78 percent and a 22C sea.