Extreme cold episodes in Mainland Portugal: intensity, spatial contrasts and synoptic causality

Abstract

Episodes of extreme cold are not frequent in Mainland Portugal and they are usually short and have a low intensity when compared with what happens in other regions of Europe on the same latitude. To demonstrate that this kind of paroxysm is characteristic of the thermal regime of Mainland Portugal, we evidentiated its frequency of occurrence in the period between 1980 and 2010 for the weather stations of Braganza, Porto, Penhas Douradas, Coimbra, Lisbon, Beja and Faro, emphasizing, this way, the spatial contrasts in the intensity of cold. One of the most intense and long episodes of cold in Portugal occurred between 7th and 16th January 1985, a period in which the lowest minimum temperatures of the studied series were recorded, in the stations of Oporto, Faro and Beja. In this work we analyze this thermal paroxysm, as an example of other recurrent episodes of cold, as far as intensity, spatial contrasts and synoptic causality are concerned.