Portugal’s Interior Regions in Record June Heat

It took only a few days of summer for mainland Portugal to remind residents—newcomers and long-timers alike—why July and August have a reputation for blistering heat. Data released by the national weather service, the Instituto Português do Mar e da Atmosfera (IPMA), show that the first serious spike arrived as early as 17 June, when the riverside village of Alvega in Abrantes climbed to 42.3 °C. Temperatures slipped briefly after that burst, but the relief did not last: on 29 June the Alentejo town of Mora reached 46.6 °C, a new all-time June record for the country and only 0.7 °C shy of Portugal’s absolute high set in Amareleja back in the summer of 2003.

The Hotspots Behind the Headlines

While coastal cities such as Porto and Lisbon rarely breach 35 °C thanks to Atlantic breezes coastal cities such as Porto and Lisbon rarely breach 35 °C thanks to Atlantic breezes, several inland locations spent the second half of June above the 40-degree mark. On 17 June alone, IPMA sensors noted 41.9 °C in the wine-growing hills of Pinhão, 41 °C in Zebreira near the Spanish border, and just over 40 °C in Mora, Lousã, Mortágua and Avis. A week later the thermometer in Alvega touched 45.4 °C before Mora’s record-breaking 46.6 °C sealed the month’s extreme status. These numbers place Portugal alongside Spain and Italy, which also issued heat alerts as parts of the Mediterranean pushed past 40 °C.

What Turned Up the Heat?

Meteorologists trace the event to a familiar summertime pattern: a powerful ridge of high pressure stretching from the Azores toward the Bay of Biscay met a trough pulling north from the Sahara. The collision trapped a dome of hot, dry air over the Iberian Peninsula, compressing and heating the lower atmosphere much like a sealed lid over a saucepan. Scientists point out that such "heat domes" are becoming more frequent and more intense as the planet warms. Climate Central estimates that temperatures of this magnitude are now three to five times more likely than they were before industrial-era greenhouse gas emissions.

The Forecast for Early July

IPMA expects the first few days of July to bring slightly calmer conditions, with maximums between 23 °C on the northwest coast and 34 °C across the interior. Evening relief, however, remains limited; minimums are predicted to stay in the mid-teens to high teens for most regions. From Thursday onward, the agency anticipates another rise that could once again nudge parts of Alentejo, the upper Douro valley and the Beira interior past 40 °C. No significant rainfall is on the horizon after mid-week.

Staying Safe When Temperatures Spike

If you are new to Portugal, remember that many residential buildings—particularly older stone or concrete structures—lack central air-conditioning. Locals cope by closing shutters during the hottest hours, taking advantage of public "zonas de sombra" (shade zones) in parks, and delaying errands until the evening "fresquinho" sets in. Keep water on hand, use the country’s well-developed municipal pool network, and watch the civil protection authority’s fire-risk map; dry vegetation combined with gusty afternoon winds turns much of the interior into potential wildfire territory between now and September.

Looking Beyond This Heat Wave

Historical records show that June is not usually Portugal’s hottest month, yet it now accounts for two of the three highest temperatures ever measured in the country. IPMA climatologists warn that intense heat episodes are arriving earlier and lasting longer, challenging both the public health system and infrastructure such as railways and energy grids. For foreign residents, that means factoring in higher summer utility bills, reconsidering travel plans during peak afternoon hours, and, perhaps most importantly, adjusting expectations of what a Portuguese summer feels like in the 2020s.