El Niño/La Niña strength
ENSO Index
Note: The ENSO Index represents a centered three-month mean sea surface temperature anomaly for the Niño 3.4 region (i.e., 5°N-5°S,120°-170°W). According to NOAA, events are defined as five consecutive overlapping three-month periods at or above the +0.5°C anomaly for El Niño events and at or below the -0.5°C anomaly for La Niña events. Horizontal lines indicate the +0.5°C and -0.5°C anomaly. Last observation is November 2025.
