The climate of Bulgaria is complicated. The north is dominated by continental air masses from the Russian steppes while the south sits at the northern limit of the Mediterranean sphere. This clash of systems can cause stormy weather to arise at any time of the year and can bring extremes of temperature in summer or winter. However, there are numerous regional variations due to topography and microclimates in the more remote valleys.
Winters tend to be long, with heavy snows in the mountains from December to May, but temperatures are slightly milder on the Black Sea coast, which sees more rain. Summers are long and hot, with an average temperature of 24°C (75°F), but higher in the west around the capital and lower in the Black Sea area, where the heat is tempered by offshore breezes.
Rain can be expected at all times of year but is a particular feature of the spring and autumn.