El Nino Watch

Measured air quality (Air4Thai)

Hourly PM2.5, PM10 and Thai AQI measured at government stations in southern Thailand.

Koh Samui watch

The Pollution Control Department's Air4Thai network. The app keeps the stations within 300 km of Samui; the nearest is Surat Thani (about 87 km). Koh Samui itself has no station. Series air4thai_<station>_pm25 and _pm10 (ug/m3) and _aqi; status key air4thai_samui = nearest station.

Limits. The nearest station is on the mainland; Samui's air is usually cleaner thanks to sea breezes. A station can stop reporting for hours; its timestamp is shown.

How to read it

Thai AQI bands: 0-25 very good (blue), 26-50 good (green), 51-100 moderate (yellow), 101-200 starting to affect health (orange), above 200 affects health (red). PM2.5 above 37.5 ug/m3 (24-hour) is above Thailand's standard. A missing value means the station does not measure that pollutant.

Why it matters for Koh Samui

El Nino dry seasons bring more fires in Sumatra, Borneo and mainland South-East Asia and so more haze. These are real measurements, a check on the model forecast (CAMS) used for Samui.

Sources

ENSO status now

ONI (NOAA CPC)
+1.80 °C, JJA 2026 (previous +1.39 °C)
RONI (NOAA CPC)
+1.36 °C, JJA 2026
Nino 3.4 weekly (NOAA CPC / OISST)
+3.0 °C anomaly, week of 16 Sep 2026 (SST 29.6 °C)