Averages along Portugal’s southern and south-western coastlines benefited from south-easterly winds from the Sahara, which have seen water temperatures rise to as much as 26.5 degrees Celsius in the Algarve. The highest sea temperature ever recorded in the region was 26.6 degrees back in 2010. The average for July was just over 22 degrees along the southern coastline, rising to 23.9 degrees in August.