ROYN — Yonaguni Airport

fog forecast & climatology · Yonaguni city page · full 10-year analysis →
No fog forecast feed exists for this station. September typically brings about 3 hours of dense fog here (10-year average).

Fog hours per year
12 h below CAT I minima (2016–2026 average)
Fog season
September and July
Typical fog event
~1 h once it forms (middle half 1–1 h, n=98)
Data through
2026-08-15 · machine-readable data.json

When this airport fogs in

In a typical year Yonaguni Airport spends 12 hours below CAT I approach minima (visibility under ~½ mile or ceiling under 200 ft), concentrated in September and July. The strip above shows the hour-by-hour pattern for the current month from ten years of weather observations.

Fog season

January: ~0 hJanFebruary: ~0 hFebMarch: ~1 hMarApril: ~1 hAprMay: ~1 hMayJune: ~1 hJunJuly: ~2 hJulAugust: ~1 hAugSeptember: ~3 hSepOctober: ~1 hOctNovember: ~1 hNovDecember: ~0 hDec
Fog season is July, September, peaking in September; fog is mostly a 2 PM–4 PM phenomenon; typically thinning out by 8 PM; a typical event lasts about 1 hour once it forms local time · 10-yr average

For flight operations

EFVS crews: the CHASE board ranks airports by live fog status, approach lighting, go-around height and flight time from your base. Forecast probabilities publish here per-airport once the calibrated model beats climatology on live verification — receipts on the scorecard. Methodology.

Sources: NOAA/NWS National Blend of Models guidance · METAR observations 2016–2026 (Iowa Environmental Mesonet) · FAA NASR. Machine access: data.json · llms.txt. Not for operational use.