Image caption
This graph shows monthly sea surface temperature anomalies (difference from average) in the Niño 3.4 region of the tropical Pacific for 2020-21 (purple line) and all other years (gray lines) starting from first-year La Niña winters since 1950. While two La Niña winters in a row is pretty common, three-peats have occurred only twice. Climate.gov graph based on ERSSTv5 temperature data.