The first heat wave of this summer arrives with temperatures over 42°C, and Aemet issues a "special warning": these will be the most affected areas.

Thermometers are set to undergo a radical change in the coming hours. After the recent respite from the drop in temperatures, the State Meteorological Agency (Aemet) has issued a special warning ahead of the arrival of the season's first heat wave, which will settle over the Iberian Peninsula and the Balearic Islands starting this Friday. The cause is a powerful mid- and high-level anticyclone originating in the interior of the African continent, which will intensify and progressively cover our territory, injecting a very warm and relatively dry air mass driven by southerly winds.

With the sunshine typical of late June , the mercury will begin its climb over the next few hours —slightly at first, with the exception of the eastern third and the Balearic Islands—before becoming more widespread on Friday and Saturday, raising both highs and lows.

The core of the wave will be located in the southern half, especially the southwest quadrant, and in the depressions of the northeast of the peninsula. Starting Saturday, temperatures are expected to exceed 38°C fairly widely in these areas , with peaks of 40 to 42°C in the valleys of the Guadiana, Ebro, and Guadalquivir Rivers. The episode will reach its peak on Sunday and Monday: values ​​above 40°C will then also extend to the Tagus Valley, while the area around the Guadalquivir could very likely exceed 42°C.

Although the northwest quadrant and the Cantabrian region will be relatively spared thanks to a cooler Atlantic flow, the heat will not be limited to the south. The northern plateau, inland Mallorca, and the Júcar and Segura valleys will reach 36°C and even touch 38°C at times, creating a very widespread heat scenario for the dates.

Along these lines, Aemet has detailed that minimum temperatures will also be unusually high: in large areas of the southern half and the Ebro Valley , temperatures are not expected to drop below 23-25°C throughout the entire episode. This means tropical—or even torrid—nights that will make it difficult to rest and increase the feeling of heat.

Models point to a gradual easing of temperatures from the west starting Wednesday. This drop is expected to be most noticeable in the northern half of the country on Thursday. However, in the southwest quadrant, the lull will be less clear , and temperatures of 38-40°C are likely to persist during those days. Therefore, the exact duration of the wave will vary by area, with a later end in western Andalusia and Extremadura.

In recent weeks, our country has recorded temperatures well above normal for June. The temperature anomaly graphs speak for themselves. This isn't a one-time occurrence. Between 2022 and 2024, seven records for exceptionally warm months have been broken. To find the last colder-than-normal month, we have to go back to February 2005, as Aemet explained on social media.

Furthermore, on the 23rd, the Almería airport station recorded two new records for the month of June: the maximum temperature reached 40.9°C and the minimum temperature remained at 27.1°C. This observatory has been collecting data since 1968.