Until 11:00am on Sunday, meteorologists predict the persistence of low minimum temperatures, with negative values in Guarda (-5º), Vila Real and Bragança (-2º).
In addition to those three districts, Aveiro, Braga, Castelo Branco, Coimbra, Évora, Leiria, Portalegre, Porto, Santarém, Setúbal, Viana do Castelo and Viseu are under a yellow warning.
As for Faro, the warning is valid until 18:00 on Sunday and is due to sea unrest, with the forecast of waves from the Southeast up to 2 to 2.5 metres on the south coast.
The yellow warning is issued by the IPMA whenever the weather situation represents a risk for certain activities.
The IPMA forecasts for today on the mainland little cloud or clear skies, increasing cloudiness in the Algarve, frost formation, especially in the interior, and a small decrease in the minimum temperature in the North and Centre.