El Nino Watch
How much warmer (+) or cooler (-) the sea surface is than its 1991-2020 normal for that date, in °C.
Indices
An SST anomaly is the sea surface temperature minus its normal for that place and date (see Anomaly). Maps of SST anomaly make El Nino easy to see: a long red tongue of warm anomalies along the equator in the eastern Pacific.
Red/orange = warmer than normal, blue = cooler, white or pale = near normal. On the Indices page, values above +0.5 in the Nino regions indicate El Nino-like warmth.