Before noon on Thursday, it will be mostly sunny, followed by cloudy skies and brief showers, mainly over western Bulgaria and the Central Balkan Mountains. In northwestern Bulgaria, the showers will continue until Friday night. It will be hot, with maximum temperatures ranging from 30°C to 35°C in Sofia and reaching around 30°C elsewhere.

In the mountains, it will be sunny before noon, with cumulus and cumulonimbus clouds developing later, particularly over the mountain ranges in western and central Bulgaria. There will be brief showers and possibly thunderstorms here. The wind will be light to moderate but will change in speed during thunderstorms. At an altitude of 1,200 metres, the maximum temperature will be around 23°C, while at 2,000 metres it will be around 16°C.

The Black Sea coast will be mostly sunny. A light south-easterly wind will blow. Maximum temperatures will be lower than in the country's interior, ranging from 24°C to 27°C. Sea temperatures will range from 18°C to 20°C, and the sea will be slightly to moderately rough (1–2 on the Beaufort scale).