Two marine heatwaves — one moderate, one severe — struck the waters off Faro, Portugal, between mid-June and early July 2026, pushing sea surface temperatures to as high as 26.1 °C, data from the Portuguese Navy's hydrographic institute shows.
The first episode was classified as moderate, with a daily peak of 23.3 °C — roughly 1.5 °C above the 90th-percentile threshold. It was followed by a stronger event reaching 24.8 °C, about 2.2 °C above normal limits, the Navy said.
Both episodes were detected by the Faro Costeira buoy, part of the MONIZEE coastal monitoring network, between 15 June and 9 July. Marine heatwaves can disrupt ecosystems and fisheries along the Algarve coast.