UNOFFICIAL GUIDE
YAEYAMA / THE SHAPE OF A YEAR
A Yaeyama year turns less on temperature than on wind, light and rites. The sea opening in spring, the season of rains, the typhoon summer, the old-calendar festivals of autumn and winter. Not “which month is best”, but what face the islands wear in each — drawn from public sources only.
FOUR FACES OF THE YEAR
Yaeyama's climate is subtropical and oceanic; the four seasons blur. Yet the year truly turns. Here are its faces, drawn only within what the JMA and the islands' official bodies say.
In March most years, “Japan's southernmost sea opening” is held in turn by Ishigaki City, Taketomi Town and Yonaguni Town. The deigo — Okinawa's prefectural flower — blooms around March to May, and the Southern Cross season is still on. The year's softest light.
By the JMA's climatological normals for Okinawa, the rainy season begins around May 10 and ends around June 21. The season of rain is also the season the forests and fields deepen. For word of Iriomote’s sagaribana — flowers that open at night and fall by morning — see the tourism association’s guidance.
JMA statistics show typhoon approaches to Okinawa are most frequent from July to September. In the sea, box jellyfish (habu-kurage) occur from May to October, and Okinawa Prefecture issues an advisory. Make summer plans together with the official sky and sea information.
In autumn, the old-calendar dates bring round Taketomi's Tanadui and Iriomote's Shichi festivals. Winter's northeasterly monsoon brings chilly days, and the sea can turn rough. In December, the Southern Cross season begins again.
A PROTECTED NIGHT SKY
The night sky over these islands is a protected one. In March 2018, Iriomote-Ishigaki National Park became Japan's first International Dark Sky Park, and in 2026 the designation became full.
The designation came from DarkSky International (formerly IDA). The 2018 designation was Japan's first, and in 2026 it moved from provisional to full. The darkness of the night itself is one of these islands' resources.
At latitude 24°N, Ishigaki sees the Southern Cross for about half the year, from December to around June — so the National Astronomical Observatory of Japan introduces it. It hangs low in the southern sky like a seasonal signal.
Ishigaki hosts the NAOJ's Ishigaki Astronomical Observatory, whose 105cm “Murikabushi” telescope watches this sky. Murikabushi is Yaeyaman for “cluster of stars” — the Pleiades.
HOW TO READ THIS CALENDAR
This page carries not one date that changes with the year. It draws only the character of island time. The actual dates and decisions always belong to the official sources.
Both Tanadui (a nationally designated Important Intangible Folk Cultural Property since 1977) and Shichi (designated 1991) are set by old-calendar dates, so their Gregorian dates change every year. Check each year's schedule with Taketomi Town.
Taketomi Town, “Tanadui Festival” ↗Rainy seasons, typhoons, advisories — normals exist, but each year differs. Judge swimming and sailing by the official information of the moment. Word of the flowers, too, shifts with the year.
Japan Meteorological Agency ↗This page names no best season. Do you want to meet the stillness, the rites, or the stars? Choose your dates by the face of the islands you want to meet. For the stay itself, the compass awaits.
Find a journey on UMI YAIMA COMPASS →This page is an unofficial, independent work. Statements on seasons, climate, rites and stars summarize the public and official sources below, confirmed on 2026-07-18 via search-result titles and summaries (the pages themselves cannot be read from this environment, so confirmation is at summary level). Dates that change with the year — festivals, advisories, blooms — are not included. Always confirm with official information at the time of travel.