Europe: High temperatures forecast to persist across southeastern regions through at least Aug. 17 /update 1

High temperatures are forecast to persist across parts of southeastern Europe through at least Aug. 17. The affected area includes much of Albania, Austria, Bosnia and Herzegovina, Bulgaria, Croatia, Greece, Hungary, Kosovo, Montenegro, North Macedonia, Romania, Serbia, and Slovenia. Maximum temperatures in excess of 40 C (104 F) are possible across parts of the region over the coming days.

As of Aug. 12, the various meteorological services for the respective countries have issued the following heat-related warnings across the region:

• Red high-temperature warnings (the highest level on a three-tier scale): Across Bosnia and Herzegovina with the exception of mountainous areas; Dubrovnik, Rijeka, and Split regions in Croatia; and Eastern Serbia, Pomoravlje, Southeast Serbia, and Southwestern regions in Serbia.
• Orange high-temperature warnings: Parts of eastern and southern and isolated pockets of north-central and western Austria; much of central, northern, and western Bulgaria; Gospic, Karlovac, Knin, and Zagreb regions in Croatia; the North East Aegean Island region in Greece; Baranya, Bacs-Kiskun, Csongrad-Casnad, Somogy, and Tolna counties in Hungary; across Kosovo; Adriatic coastal and central regions in Montenegro; across North Macedonia; across the rest of Serbia not under red warnings; and central, southeastern, and southwestern regions in Slovenia.
• Yellow high-temperature warnings: Across the rest of Austria not under orange warnings; across the rest of Bulgaria not under orange warnings; Osijek Region in Croatia; across much of the rest of Greece not under orange warnings; across the rest of central and western Hungary not under orange warnings; northern mountainous and continental regions of Montenegro; parts of southern and western Romania; and northeastern and northwestern regions in Slovenia.

Further red, orange, and yellow high-temperature warnings are in place across parts of the region Aug. 13-16. Officials could update and 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 threaten 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.