A heat wave is coming to Spain and Portugal later this week. Much of Portugal as well as central, southern and western Spain are looking at daytime highs exceeding 40 °C and locally potentially even at 45 °C!

The pattern in the second half of this week will support a strengthening upper ridge from SW into west-central Europe, so stable and hot conditions are expected. As center of the ridge will be close to the western Europe, the flow will allow an extremely warm airmass to advect and maintain over Iberian peninsula.

850 mb (approximately 1500 m above sea level) temperature peaking at 30-31 °C which is very extreme for any place in Europe:

Various models are hitting extremely high afternoon temperatures from Thursday, Aug 2nd until Sunday, Aug 5th – locally even above 45°C per some models. Best model guidance suggests the peak of the heat wave will be over south-central Portugal and WSW Spain on Friday and Saturday.

GFS model (July 30 guidance):

ARPEGE model (July 30 guidance):

GFS model (July 29 guidance):

One of the greatest concerns in these areas is the potential setup for dangerous wildfires as the pattern favours ENE winds across Iberian peninsula, so windy and locally very dry airmass will be present. Such environment will be exceedingly favourable for explosive spreading of wildfires.