Marine heatwave forecasts – June 21, 2025 – Re-posted from Mercator Ocean Bulletin

Marine heatwave categories for 21 June 2025 (global ocean). Credit: Mercator Ocean International

The marine heatwave bulletin provides forecasts and analysis of marine heatwave events across the globe and throughout the year. Used datasets include observations (satellite sea surface temperature maps) and numerical model analyses (assimilating satellite and in situ observations) to derive marine heatwave forecasts for a 10-day period. This week’s forecasts were produced using as a comparison the marine heatwave situation on 10/06/2025.

Category and geographical extent differences for 21 June 2025 (global ocean). Credit: Mercator Ocean International

Tropical Atlantic

The marine heatwave in the Gulf of Mexico is decreasing in extent, but its intensity remains within the strong categories. The marine heatwave stretching from the eastern coast of Florida to the offshore waters of Europe is intensifying, with a larger area falling into strong categories.

Water surface temperature anomaly map for the week 15 to 21 June, 2025. Global Ocean. Credit: Mercator Ocean International