Marine Heatwave Bulletin Forecasts for August 15, 2026 – Reposted from Mercator Ocean International

Marine heatwave category forecasts for 15 August, 2026 for the Global Ocean. Data: GLO12 forecast. Source: Copernicus Marine Service/Mercator Ocean International.

GLOBAL OCEAN

North Atlantic

The marine heatwave affecting the middle of the basin, around 30°N, is increasing in intensity but remains stable in extent.

Pacific Ocean

  • The marine heatwave in the southern Bering Sea (around 50°N) remains stable in terms of area but is increasing in intensity, with conditions still ranging from moderate to strong, and even extreme in some areas. 
  • The marine heatwave around Japan is decreasing in both extent and intensity, and only a few scattered areas of moderate intensity remain. 
  • The marine heatwave extending across nearly the entire equatorial band from 30°S to 30°N is increasing in intensity, especially between 180°W and 80°W where severe to extreme intensities are reached in several areas. 
  • The marine heatwave to the west and south of New Zealand remains stable in both area and intensity.  

Indian Ocean

The marine heatwaves west of Madagascar and in the central part of the basin remain stable in intensity, still ranging from moderate to strong, while those in western part of the basin are increasing in intensity, and those in the eastern part are decreasing in extent. 

Southern Ocean

The marine heatwave, extending from 50°E to 80°E in longitude and 45°S to 60°S in latitude, remains stable in both area and intensity, with conditions still ranging from moderate to strong. 

Weekly temperature anomalies

Weekly mean sea surface temperatures Anomaly 9-15 August 2026

Mediterranean Sea0°C to >3°C 
North Atlantic-2 °C to >3°C 
Pacific Ocean-2°C t >3°C 
Indian Ocean-2°C to 2°C  
Southern Ocean-1°C to 2°C