Southeastern Europe: High temperatures forecast to persist across the region through at least June 24 /update 1

High temperatures are forecast to persist across much of southeastern Europe through at least June 24. The affected area includes Albania, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Kosovo, Montenegro, North Macedonia, Romania, Serbia, and Slovenia. Temperatures of over 40 C (104 F) are possible in parts of the region over the coming days, with the peak of the heatwave expected around June 21. As of June 19, the Republic Hydrometeorological Service of Serbia has issued red high-temperature warnings (the highest level on a three-tier scale) for eastern and southeastern regions June 19-20, Kosovo June 20, and across much of Serbia and Kosovo June 21. Authorities from the respective regional meteorological services have issued orange and yellow high-temperature warnings across much of the affected area over the coming days. Officials could update and possibly extend the coverage of weather alerts over the coming days.

The high temperatures may result in increased energy and water demand and a heightened risk of heat-related illnesses, such as heat exhaustion and heat stroke.

The extended period of oppressive heat and dry conditions may produce ideal circumstances for wildfire growth throughout the region. Heatwaves also pose a threat to vulnerable groups - such as the elderly, children, pregnant women, and those with respiratory illnesses - due to the increased possibility of heat stroke or heat exhaustion during prolonged exposure to high temperatures. These health risks could also extend to relatively healthy individuals during significant heatwave events.

Very high temperatures may warp rail tracks and force passenger and freight trains to operate at reduced speeds. Road surface damage is also possible, and overheated vehicles may worsen traffic problems in urban areas where congestion is already a problem. Commercial trucking disruptions might occur as very high temperatures stress vehicles, making tire blowouts more common. Major flight disruptions are unlikely, but general aviation disruptions are possible, and some airfreight carriers could reduce cargo loads. High temperatures could lead to an increased demand for electricity, which might trigger localized brownouts or blackouts, exacerbating hazardous conditions when air conditioning is no longer possible.