Bulgaria’s climate is increasingly mirroring that of northern Greece, climatologist Simeon Matev told BTA, noting that the country has seen record-breaking temperatures become almost routine over the last seven to eight years. This summer’s highest temperature reached 43.5°C in Montana.

Matev explained that areas like Sandanski in Southwest Bulgaria, along with Haskovo and Kardzhali in the south, now experience average temperatures similar to those recorded in Greek cities three to four decades ago. He pointed out that Sofia’s average annual temperature has risen to levels comparable with Blagoevgrad in the southwest, while Blagoevgrad’s climate itself resembles that of Sandanski.

While Bulgaria has not hit an absolute temperature record this year, Matev warned that heatwaves are becoming increasingly prolonged. He described stretches of days where temperatures remain stubbornly high, rarely dipping below 35-40°C.

Of particular concern are the so-called tropical nights, where temperatures at night stay above 20°C, preventing the body from properly cooling down and resting. This prolonged heat exposure leads to physical exhaustion and heightened vulnerability to illness, alongside decreased productivity.

Certain jobs, like tram drivers, are especially exposed to the intense heat. In Sofia, efforts are underway to improve conditions by installing air conditioning in driver cabins: 11 trams will have these systems by the end of 2025, with 40 more expected to be upgraded by September 2030. Matev noted that when outside temperatures hit 40°C, the interior of a tram driver’s cabin can soar to 55°C, with a recorded maximum of 62°C.

Currently, 67 railcars come factory-equipped with air conditioning both for drivers and passengers, and all electric buses and trolleybuses in Sofia are fully air-conditioned.

Tram driver Aleksander Trifonov shared that some older trams only have air conditioning in the driver’s cabin, and sometimes heat exposure makes drivers feel unwell.

Overall, the trend toward hotter summers and longer heatwaves in Bulgaria poses growing challenges for public health and worker safety, emphasizing the need for continued adaptation measures.