According to the Portuguese Institute of the Sea and Atmosphere (IPMA), the districts of Coimbra, Leiria, Santarém, Lisbon, Setúbal and Faro (until 18:00 on Friday) will be under a yellow warning, the least serious, from 09:00 on Thursday, in addition to Castelo Branco, Portalegre, Évora and Beja, where the warning will extend until Saturday.

As of 09:00 on Friday, the IPMA will add the yellow warning due to heat to the districts of Guarda, Bragança and Vila Real.

The only districts with no warnings for these days are Viana do Castelo, Braga, Porto, Aveiro and Viseu.

A yellow warning is issued when there is a risk situation for certain activities depending on the weather.

A small rise in maximum temperatures is expected today, especially in the North and in the interior of the Central region.

Castelo Branco, with 34º Celsius, will be the hottest district, and Aveiro, Sines and Sagres (24º) will be the coolest today, but from Thursday onwards temperatures will start to rise and are expected to fluctuate between 38º and 40º in the interior of the country.