site.btaWeather in September: Temperatures to Range between 5C and 36C

The lowest temperatures in Bulgaria in September 2025 will be between 5C and 10C, Mariyana Popova of the National Institute of Meteorology and Hydrology told BTA on Sunday. The highest temperatures will be between 31C and 36C. The Black Sea coast will see relatively higher temperatures.

The average monthly temperature in Bulgaria in the next 31 days will be around the month’s norm, which is between 17C and 20C or between 3C and 10C in the mountains, or slightly higher.

The amount of precipitation will be around the usual levels, which for September are between 40 and 60 litres per square metre, or lower. For the mountains, the norm is 60 to 80 litres per square metre.

During the first 10-day period of the month, the weather will be mostly sunny with cumulus and cumulonimbus clouds in the afternoon. Rain showers will be scarce, but slightly more likely on September 4, 7, and towards the end of the period. Temperatures will be higher than usual but will start to drop after September 4.

Sunny weather and temperatures above the usual are also expected in the last 20 days of the month. Precipitation is more likely from September 18 to 20 and from September 23 to 25.