Turkey faced a severe heat wave on Aug. 9, 2025, with felt temperatures exceeding 40°C across the country [1].

This extreme weather event created dangerous living conditions for millions of residents, particularly in urban centers like Istanbul and Adana, where high humidity compounded the heat. The combination of temperature and moisture levels posed significant risks to public health and daily infrastructure.

Nationwide, the felt temperature reached 40°C [1]. In the city of Adana, the situation was more extreme, with felt temperatures exceeding 55°C [2]. This mark represented the hottest day recorded in Adana in 95 years [2].

Humidity played a critical role in the severity of the event. Relative humidity rose to the 70% range [1]. This level of moisture made it difficult for residents to breathe and hampered the body's natural ability to cool down through perspiration.

The heat wave affected various regions of the country, but the impact was most notable in Istanbul and Adana [1, 2]. Residents in these areas struggled with the oppressive atmosphere as the region dealt with the year's hottest day [1].

Local reports said that the atmospheric conditions created a stifling environment. The synergy of the 70% humidity [1] and the soaring temperatures created a high heat index, which significantly increased the risk of heat-related illnesses across the Turkish population [1].

“Felt temperatures in Adana exceeded 55°C”

The disparity between nationwide averages and the localized peak in Adana highlights the volatility of regional heat pockets during extreme weather events. When humidity reaches 70%, the human body cannot effectively dissipate heat, transforming a severe heat wave into a critical public health emergency.