Pattern evolution and latest model guidance are well on track for the development of an intense heat wave in the second half of this week across Spain and Portugal. We take a look at the latest model guidance.

As already evident in GFS model guidance over the past few days, the entire region will experience an intense heat wave, with temperatures pushing into mid to high-40s, quite possibly breaking all-time records. The pattern will be optimal for extreme heat, as mutliple factors combine. GFS even hints at peaks of 50-51 °C, however, this may well be the effect of the relatively low resolution of the model.

Models currently agree on the hottest day being on Saturday. It will be very hot from Thursday on and also on Sunday, but the temperatures will be several degrees lower (see maps at the end of the article). We now take a closer look at various model guidance for Saturday.

GFS still suggests temperatures as high as 50-51 °C. Again, this may well be the effect of the low resolution of the model. On the other hand, synoptic and mesoscale situation will be favourable for record-setting heat.

Peak temperatures across Portugal and Spain on Saturday. GFS model guidance. Map: wxcharts.eu.

ARPEGE and ICON-EU all indicate temperatures in the upper 40s, peaking at 47 °C.

Peak temperatures across Portugal and Spain on Saturday. ICON-EU model guidance. Map: wxcharts.eu.

Peak temperatures across Portugal and Spain on Saturday. ARPEGE model guidance. Map: wxcharts.eu.

Next we take a look at relative peak temperatures on each day of the heat wave.