El Nino Watch

Global sea surface temperature, daily (ERA5, 60S-60N)

era5_sst_6060 and era5_sst_6060_anom.

Indices

Daily mean sea surface temperature between 60S and 60N from Copernicus Climate Pulse, and its difference from 1991-2020.

Limits. Last 2-3 days preliminary. Not the same dataset as the OISST world SST series.

How to read it

degC; around 21.0 degC and +0.7 in late September 2026.

Why it matters for Koh Samui

Ocean heat drives air temperature and coral bleaching risk; El Nino raises it.

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)