The climate of Kyustendil is continental, with cold winters and warm summers.
The city is located in the far west of Bulgaria, a short distance from the border with Serbia and Northern Macedonia, and at 560 meters (1,840 feet) above sea level. The climate is not very different from that of Sofia, given that the city is not far away and at the same altitude, although it is a bit milder because it is surrounded by high mountains from which warm, foehn-like winds can descend.
The average temperature of the coldest month (January) is of 0 °C (32 °F), that of the warmest month (July) is of 21.5 °C (71 °F). Here are the average temperatures.
Kyustendil - Average temperatures
Min (°C)-5-4049121413950-3
Max (°C)581318232729302519116
Min (°F)232532394854575548413227
Max (°F)414655647381848677665243

Precipitation amounts to 560 millimeters (22 inches) per year: so, it is at an intermediate level. It ranges from 30 mm (1.2 in) in the driest month (January) to 60 mm (2.4 in) in the wettest (June). Here is the average precipitation.
Kyustendil - Average precipitation

On average, there are around 2,180 sunshine hours per year. Here are the average sunshine hours per day.
Kyustendil - Sunshine


Best Time

The best time to visit Kyustendil is from mid-May to late September, keeping in mind that it can sometimes be hot in July and August, and more rarely in the second half of June, so those who don't like the heat can avoid these periods. You should also take into account some afternoon thunderstorms, in addition, it's better to bring a sweatshirt for the evening, and maybe even a jacket if you go in May or September.