From Friday, 21 August 2026, the weather in Spain will undergo a major change: a low deepening over the Atlantic will bring colder air to the Iberian Peninsula and significantly increase the likelihood of thunderstorms. According to AEMET temperatures in many regions will fall below what is usual for late August, while the risk of heavy rainfall will rise. Protection agencies such as Protección Civil advise people to watch for short-notice warnings.
The drop in temperature will be most pronounced in the north and north-east. According to José Antonio Maldonado (Meteored) highs in Galicia, Asturias, Cantabria, the Basque Country and Navarre will often be just 21 to 25 degrees, and around 23 to 30 degrees in the northern interior. In parts of the south-west, temperatures may edge up to 30 to 33 degrees, while the south-east — for example, the area around Murcia — will remain summery for now, locally reaching 35 degrees. Overall, forecasting services report falls of up to around ten degrees compared with the start of the week.
The marked change in the weather is caused by a combination of an Atlantic low and cool air at altitude. Meteorologists believe a DANA may also develop as the situation unfolds. This combination is expected to bring locally intense storms with high rainfall rates, particularly in areas favoured by the terrain and along the northern coast. The areas most affected will be Galicia, Asturias, Cantabria, the Basque Country, Navarre and the north-east, including inland parts of Catalonia. The precise distribution of the strongest cells depends on the models and may shift at short notice.
Depending on how the situation develops, AEMET may activate regional warning levels (avisos). Possible consequences include local flooding, flash floods in narrow valleys, short-lived disruption to traffic, gusty winds and small hail. Residents and travellers should follow official advice and adjust exposed outdoor activities in the areas expected to be worst affected. Specific rainfall totals at individual stations and exact minimum and maximum temperatures are forecast values and depend on further developments; confirmed readings will only be available once the weather events have occurred.
The change follows very high temperatures at the start of the week. While Atlantic incursions of cool air at altitude are less common in late summer, they do recur. On the basis of current information, AEMET expects below-average temperatures across much of the country over the coming days, before values are likely to return to seasonal levels in some regions. Statements about the duration and intensity of the cold spell remain subject to AEMET’s ongoing assessment and further analysis by Meteored.
Editor: Andreas M. Brucker (Article created with AI assistance).