Processed monthly mean data from regular measurements of air temperature, relative humidity, and precipitation at a climate observatory (station) from 1899 to 2024, in Stara Zagora, Bulgaria

Stara Zagora station, Bulgaria (coordinates: latitude/longitude: 42.386759°N/25.647005°E, altitude 168 m), is part of the climate network of 32 stations across the country, managed by Bulgaria's National Institute of Meteorology and Hydrology (NIMH). NIMH has an agreement with the local Thracian University, which uses part of the university's base on the outskirts of Stara Zagora for the local climate station. According to the agreement, the station regularly provides meteorological information to interested researchers from the university. The station provides the university with the following data: 1. Air temperature in degrees Celsius, measured in a meteorological cell 2 m above the ground surface - daily values and monthly average; 2. Relative humidity in %, measured in a meteorological cell 2 m above the ground surface – daily values and monthly average; 3. Precipitation in mm (l/m2) – measured with a rain gauge, daily values, and monthly sum. This information was used for research about global warming, and annual values were additionally calculated.