The global oceans have reached unprecedented average surface temperatures as El Niño strengthens. On a recent Saturday, the average sea-surface temperature touched 21.1 degrees Celsius, or approximately 70 degrees Fahrenheit, according to the European Union’s Copernicus Climate Change Service. This slightly surpassed the previous daily record of 21.09 C noted in March 2024.

“The timing of this record is noteworthy,” stated Copernicus. Global ocean temperatures usually peak in March and April, following the austral summer. However, this new record emerged in August.

Alex DaSilva, an AccuWeather meteorologist, explained to Newsweek that the record pertains to oceans outside the polar regions, indicating warmth across multiple basins. A lot of this has to do with El Niño, he noted. Since El Niño significantly affects the Pacific Ocean, records tend to be broken during these periods. The Atlantic basin also remains warm, contributing to this global record.

Copernicus has previously reported that temperatures outside the polar regions have lingered between 0.35 C and 0.73 C above the long-term average over the past three years. In June, temperatures were already setting records corresponding with the onset of El Niño in the equatorial Pacific.

Highest Recorded Ocean Temperatures

The peak daily average temperature for the world’s oceans outside polar regions stood at 21.1 C or about 70 F on August 22, 2026. This figure surpassed the previous record of 21.09 C. In August 2023, the highest was 20.98 C, as reported by Copernicus.

Samantha Burgess, climate strategic lead at the European Centre for Medium-Range Weather Forecasts, emphasized, This record is a clear indication of an ocean under heightened stress. El Niño adds heat to the system on top of decades of human-driven warming. As ocean temperatures rise, the risks to marine ecosystems and coastal areas climb. The number of marine heatwave days has more than tripled since the early 1990s, increasing strain on marine life and reliant communities.

DaSilva noted that the records for the second and third-highest temperatures belong to 2024 and 2023, respectively. El Niño persisted from late 2023 into early 2024 before transitioning to La Niña.

March and August typically mark the peak warmth of the world’s oceans, DaSilva said. While waters could continue warming briefly, setting further records in September is unlikely.

Understanding El Niño and Its Potential Strength

El Niño represents the warm phase of the El Niño-Southern Oscillation (ENSO), a natural climate pattern in the tropical Pacific that shifts irregularly every two to seven years. During El Niño, central and eastern equatorial Pacific waters warm, trade winds weaken, and tropical rainfall patterns move eastward. These changes may disrupt global weather and climate patterns, as stated by the National Oceanic and Atmospheric Administration (NOAA).

NOAA’s Climate Prediction Center indicated on August 13 that El Niño is intensifying, with a more than 90 percent likelihood of a strong event during the Northern Hemisphere fall and winter of 2027. They predicted a 69 percent chance of a historic El Niño event during the October-December 2026 season, surpassing previous events dating back to 1950.

DaSilva speculated that another ocean record might occur with the seasonal peak. Depending on El Niño’s strength this fall, we might break the sea-surface temperature record again next March, he said, referencing how 2024’s record occurred in March by the end of an El Niño.