A file photo from Sofia Photo Agency shows a Bulgarians looking for rescue from the scorching heat.
Code yellow has been declared for 17 Bulgarian regions for Friday over the forecast for dangerous heat.
The forecast is issued by the National Institute for Meteorology and Hydrology at the Bulgarian Academy of Sciences, BAS.
The regions under code yellow are: Vidin, Vratsa, Montana, Pleven, Lovech, Kyustendil, Veliko Tarnovo, Ruse, Blagoevgrad, Targovishte, Pazardzhik, Plovdiv, Yambol, Stara Zagora, Haskovo, and Kardzhali.
Temperatures are to reach anywhere between 33 and 38 degrees Celsius, about 33 in the capital Sofia.
Code yellow means potentially dangerous weather, where the forecast is not for unusual meteorological events, but requires people to exercise caution.