The Barlavento Algarve basin continues to be the one with the lowest amount of reserve water, falling from 22.3% in May to 20.8% in June.

At the end of June, the Mira basins also had less water availability, with 40.5% (41.4% in May) and Arade 40.8% (42.7% in May).

The amount of water also fell in the Lima basins, from 76.1% to 53.5%, and in the Sado basin, from 72.3% to 66.7%.

On the last day of June, the Mondego (91.3%), Guadiana (87.4%), Cávado (87%), Oeste (85.7%), Douro (80%) and Tejo (77.9%) basins had the highest volume of water.

According to SNIRH data, of the 58 monitored reservoirs, 28 had water availability above 80% of the total volume and another six below 40%.

June 2024 storage by river basin is higher than the June storage averages (1990/91 to 2022/23), except for the Lima, Mira, Ribeiras do Algarve, and Arade basins.

Each river basin may have more than one reservoir.

According to the Portuguese Institute of the Sea and Atmosphere (IPMA), almost half of the territory of mainland Portugal was in a weak or moderate meteorological drought at the end of May, with a greater focus on the southern region.