LISBON, July 4 (Xinhua) -- Portugal has just recorded its third hottest June on record, with experts warning that extreme heat events may become increasingly frequent and intense, potentially signaling a "new normal" for future summers.

A severe heatwave swept across the Iberian Peninsula in late June, pushing temperatures to record-breaking levels. According to the Portuguese Institute for the Sea and Atmosphere (IPMA), the inland town of Mora in the Evora district reached a scorching 46.6 degrees Celsius on June 29, the highest temperature ever recorded in Portugal during June.

IPMA data confirmed that June 2025 was the third warmest and the fourth driest June since national records began.

Portuguese climatologist Jose Alvaro Silva said climate change is driving an increase in the frequency and intensity of early-season heatwaves. "These events are becoming part of our new climate reality," he said. Silva explained that the recent heatwave was triggered by a mass of hot air from North Africa, trapped over the region by a high-pressure system, a phenomenon known as a "heat dome." High sea surface temperatures in the Mediterranean and persistent lack of cloud cover further fueled the extreme heat.

Ricardo Trigo, a climatologist at the University of Lisbon and a longtime expert on heatwaves, cited two key amplifying factors: parched soil and abnormally warm Mediterranean waters. "If two years from now we again see warm Mediterranean seas and severe winter-spring drought over the Iberian Peninsula, the resulting heatwave could be even more intense than this one," he warned.

The Portuguese Directorate-General of Health reported on Thursday that 69 excess deaths occurred nationwide during the heat alert period, which began on June 28. Most of the victims were aged 85 and above.

Silva added that seasonal forecasts predict continued above-average and even well-above-average temperatures in July and August, creating favorable conditions for further heatwaves. He emphasized that this trend is likely to persist in the coming decades. ■