{"id":6189,"date":"2026-09-02T15:37:38","date_gmt":"2026-09-02T06:37:38","guid":{"rendered":"https:\/\/en.gogo-tour.com\/info\/ishigakijima-september-weather\/"},"modified":"2026-09-02T16:38:49","modified_gmt":"2026-09-02T07:38:49","slug":"ishigakijima-september-weather","status":"publish","type":"post","link":"https:\/\/en.gogo-tour.com\/info\/ishigakijima-september-weather\/","title":{"rendered":"Ishigaki Island in September: Weather, Manta & Typhoon Guide"},"content":{"rendered":"

Ishigaki Island in September \u2014 Summer Sea Still Open, But Watch Typhoons & Jellyfish<\/h2>\n

Quick answer:<\/strong> September on Ishigaki Island keeps the full summer feel \u2014 average air 28.2\u00b0C (82.8\u00b0F), sea 28\u00b0C+ (82\u00b0F+), 6.3 sunshine hours per day<\/span> \u2014 with warm ocean swimming still at its best. The trade-off: 259mm (10.2 in) of rainfall, tail-end typhoon season, and the last month of Okinawa’s habu jellyfish alert (through Sep 30)<\/span>. On the upside, Kabira Ishizaki Manta Scramble hits its annual peak in Sep\u2013Oct \u2014 the “grand dance” when 10+ manta rays are sighted at once<\/span>, making it the best month of the year for divers. Flights and hotels drop 30\u201340% versus August peak<\/span>, except for Japan’s Silver Week (Sep 19\u201323, 2026) \u2014 Respect for the Aged + Citizens’ Holiday + Autumnal Equinox back-to-back, creating a 5-day national holiday.<\/p>\n

Ishigaki Island sits about 410 km (255 mi) southwest of Okinawa’s main island \u2014 closer to Taipei than to Naha \u2014 and is the gateway to the Yaeyama Islands<\/span>, Japan’s southernmost tropical archipelago. Manta ray reefs, red-tiled Ryukyu villages on Taketomi Island, and Iriomote Island’s UNESCO-listed jungle await. It’s the “Maldives of Japan,” and September is a fascinating month to visit.<\/p>\n

Because Ishigaki lies far south of Okinawa’s main island, September brings hotter days, heavier rain, and a higher chance of being the first landfall point for typhoons<\/strong> tracking north from the Philippines or Taiwan. Prepared travelers get the best of both worlds \u2014 full-summer diving conditions at shoulder-season prices.<\/p>\n

This guide covers Ishigaki September weather, typhoon statistics, jellyfish safety, peak manta ray season, Yaeyama island-hopping, food, and rental-car tips \u2014 for international travelers flying in from Tokyo, Osaka, Naha, Taipei, or elsewhere.<\/p>\n

Before you go, check the Okinawa Typhoon Guide 2026<\/a> and lock in your Okinawa rental car<\/a> early \u2014 the Ishigaki branch is minutes from New Ishigaki Airport. September’s headline attraction, the Ishigaki manta ray dives and island tours<\/a>, sells out fast \u2014 book at least 2 weeks ahead.<\/p>\n

\n

At a Glance \u2014 Ishigaki Island September Weather<\/h2>\n

Everything you need for packing and planning, in one table.<\/p>\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
Metric<\/th>\nValue<\/th>\nWhat it means for you<\/th>\n<\/tr>\n<\/thead>\n
Average air temp<\/strong><\/td>\nAvg 28.2\u00b0C (82.8\u00b0F)<\/span> \/ High 31.0\u00b0C (87.8\u00b0F) \/ Low 26.0\u00b0C (78.8\u00b0F)<\/td>\nFull summer, tropical nights<\/td>\n<\/tr>\n
Sea temperature<\/strong><\/td>\n28\u00b0C+ (82\u00b0F+)<\/span><\/td>\nSame as July\/August \u2014 swimming still ideal<\/td>\n<\/tr>\n
Humidity \/ heat index<\/strong><\/td>\nAvg humidity 76%<\/span> \/ feels like 33\u00b0C+ (91\u00b0F+)<\/td>\nHot & humid \u2014 hydrate constantly<\/td>\n<\/tr>\n
Rainfall \/ sunshine<\/strong><\/td>\n259.7 mm (10.2 in)<\/span> \/ 6.3 hrs sunshine per day<\/td>\n30 mm more than Miyakojima due to typhoons<\/td>\n<\/tr>\n
Wind speed<\/strong><\/td>\n5.3 m\/s (12 mph)<\/span>, prevailing NNE<\/td>\nWindy Yaeyama coast \u2014 rain jacket beats umbrella<\/td>\n<\/tr>\n
UV index<\/strong><\/td>\nPeak 10\u201311 (very high to extreme)<\/span><\/td>\nSPF 50+ and a rash guard are non-negotiable<\/td>\n<\/tr>\n
Water visibility<\/strong><\/td>\nApprox. 20\u201330 m (65\u2013100 ft)<\/span><\/td>\nNo rivers to muddy water; a few days murky post-typhoon<\/td>\n<\/tr>\n
Beach-day rating<\/strong><\/td>\n\u2b50\u2b50\u2b50\u2b50 (great, mind jellyfish & typhoons)<\/td>\nExcellent temp & clarity, read safety section<\/td>\n<\/tr>\n
Typhoon risk<\/strong><\/td>\nTail end of peak season<\/span><\/td>\nYaeyama is often the first landfall zone<\/td>\n<\/tr>\n
Manta ray dives<\/strong><\/td>\nAnnual peak Sep\u2013Oct<\/span> (“grand dance” season)<\/td>\nKabira Ishizaki Manta Scramble<\/td>\n<\/tr>\n
Best travel window<\/strong><\/td>\nLate-September weekdays (Sep 24 onward, post-holiday)<\/td>\nAvoid Sep 19\u201323 Silver Week (5-day holiday)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Keep this table in mind and you’re 90% ready. Now for the details.<\/p>\n

\n

Weather Overview \u2014 Hotter and Wetter Than Miyakojima<\/h2>\n

\"Emerald<\/p>\n

Even within Okinawa Prefecture, as you move southwest from Naha to Miyakojima to Ishigaki, temperature, sea temperature, and rainfall all climb slightly.<\/strong> Here are the key September numbers for Ishigaki Island (JMA 1991\u20132020 normals):<\/p>\n