Climate and monthly weather forecast
Bulgaria

Bulgaria has diverse and complex climate types. Large sections of the north-central, south-central, and southeast regions have a humid subtropical climate (Köppen climate classification Cfa). A sizeable portion in the west, northeast, and central regions displays an oceanic climate (Köppen Cfb). Patches in the central and southwest regions have a warm-summer humid continental climate (Köppen Dfb). Few areas in the highest mountains have a subarctic (Köppen Dfc) and alpine climate (Köppen ET). The southernmost region exhibits a Mediterranean climate (Köppen Csa, Csb) with warm, dry summers and cold, wet winters. Bulgaria lies in southeastern Europe and shares borders with Greece and Turkey in the south. Serbia and North Macedonia are in the west, Romania in the north and the Black Sea in the east. The Atlantic Ocean, the Mediterranean and Black Seas, and the Balkan Mountains influence the climate.

Bulgaria lies at 43°N in the temperate latitudes in the eastern quadrant of the Balkan Peninsula. The topography is highly variable, with plains, hills, mountains, gorges, basins, and river valleys, even within small regions. The Danube Plain, the Balkan Mountains, the Transitional Area, and the Rhodope, are the four main climatic regions from north to south.
The snowy peaks of the Balkan Mountains give way to warm Mediterranean influence in the valleys of Macedonia and lowlands and plains of southern and upper Thrace. The continental Danube Plain in the north differs significantly from the mild and sunny Black Coast. The Balkan Mountains stretch from west to east and are a barrier between the northern cold air and warm southern air. The coastline stretches up to 220 miles, and the Iskar is the longest river at 229 miles. Musala is the highest peak in Bulgaria at 2925 meters above sea level.

Summers are hot in the interior plains of Bulgaria based but warm in the mountains. Temperatures are usually in the range of 29.4°C (84.9°F) to 32.2°C (90°F) during the day but occasionally cross 37.8°C (100°F). Winters are cold everywhere and especially severe in the north. The cold air from Russia brings low temperatures, strong winds, and severe frosts. Fog is standard in the low valleys, and temperature inversion is regular. Cold air stagnates on the ground in the valleys and plains. The skies are cloudy, and there is plenty of snowfall. Spring is relatively dry but has variable weather. Temperatures often change quickly due to the alternate invasion of warm and cold air masses. Cold days and snow shores mostly end by May. The autumn has mild and pleasant weather in the first half of the season. Cold conditions dominate the second half of the fall season by the turn of October. Bulgaria has a mean annual temperature of 10.6°C (51.1°F). The climate ranges from alpine in the high mountains to subtropical in the south.

The annual average rainfall in Bulgaria is a moderate 685.8mm (27"). Dobrudzha is the driest region with 457.2mm (18"), while the western Balkan Mountains receive the highest precipitation of 2336.8mm (92") annually. The precipitation varies by altitude, from 660.4mm (26") in the plains to 1016mm (40") in the high mountains. Northern Bulgaria receives the highest rainfall in May and June, while the southern region registers peak precipitation in the winter. Snowfall ranges from 762mm (30") to 1016mm (40") in the lowlands to over 2540mm (100") in the mountains. Snow cover lasts up to 9 months in the mountains but exists on the ground for only 30 days in the plains. The average monthly relative humidity ranges from a low of 70% in July to a high of 80% in January. The annual sunshine varies from 1700 hours in the north to 2500 in the south. The sea temperatures range between a cold 7.2°C (45°F) in the winter to a warm 25°C (77°F) in the summer.

The highest temperature on record in Bulgaria is 45.2°C (113.4°F) in Sadovo, set on August 5, 1916. The lowest temperature on record is -38.3°C (-36.9°F) in Tran, set on January 25, 1947.

The best time to visit Bulgaria is from mid-May to mid-June in the spring and mid-September to mid-October in the autumn. The days are long and devoid of cold and snow. The late spring has stable and sunny weather, with occasional thunderstorms. The early autumn is still warm and dry. Spring vacations are great to witness the flowering period, while autumn holidays are best for vibrant colors. Beach holidays are best during the summer, with warm waters on the east coast. Summer is hot, especially in the interior plains, and sees crowds everywhere.

The worst time to visit Bulgaria is in the winter from December to February. Severe cold and substantial snowfall occur in much of the country. The high mountains are particularly vulnerable to extreme cold. The low temperatures drop below freezing in many places and below -17.8°C (-0°F) in the highest mountains. However, winter excites snow lovers and adventure seekers, with activities ranging from snowboarding, snowshoeing, and skiing, among many others. Seawater temperatures are cold below 7.2°C (45°F) and not suitable for swimming. Winter is prone to ice, frost, and fog. The days are short are the skies are dark in the cold season in Bulgaria.

Bulgaria faces weather hazards, such as floods, droughts, earthquakes, and landslides. Wildfires occur in the southwest region during the summer and early autumn. Droughts occur regularly due to a moderate amount of rainfall. Most rivers are short and shallow. Flooding occurs in low-lying areas during periods of heavy rainfall. The mountainous region is prone to earthquakes of moderate intensity. Landslides are common during the wet season. Thunderstorms occur from late spring to early autumn and peak during the summer. Snowstorms pose a threat during the winter in the highlands.

January is usually the coldest month of the year in Bulgaria, with ample snowfall and dark skies. The north, central, and southwest mountain regions are colder than the rest of the country. Sofia, the capital, sees cold days and frigid nights between -5.6°C (21.9°F) to 3.9°C (39°F), with 203.2mm (8") to 254mm (10") of snowfall. Weather in January »

February is cold and snowy in the winter in Bulgaria. The average temperatures are in the cold range of -5°C (23°F) to 9.4°C (48.9°F) in much of the country except for frigid temperatures at altitudes above 1000 meters. The daytime highs generally register up to 15.6°C (60.1°F) and nights drop to -11.1°C (12°F). The Balkan Mountains accumulate between 762mm (30") and 1270mm (50") of snow in 15 snowy days in the month. Weather in February »

March brings cold to mild temperatures in the early spring season in Bulgaria. Cold fronts from the Russian North and warm air masses under the Mediterranean influence bring generally unstable conditions. The precipitation registers above 38.1mm (1.5"), with at least 10 wet days in March. Weather in March »

April is cold in the first half of the month in Bulgaria and has unstable weather. The conditions mellow significantly as the temperatures gradually rise in the plains. Ruse and Pleven on the Danubian Plain register average temperatures in the mild 6.1°C (43°F) to 17.8°C (64°F) zone. Weather in April »

May is mostly sunny and beautiful in Bulgaria, with pleasantly warm temperatures. The average low temperatures rise from 7.2°C (45°F) to 13.3°C (55.9°F) over the month. Daytime temperatures usually average below 20.6°C (69.1°F) in the first half of May and are above 26.1°C (79°F) by the month-end. Weather in May »

June brings the bright summer season in Bulgaria amid a moderate amount of rain. The average temperatures vary in the wide range of 11.1°C (52°F) to 29.4°C (84.9°F), based on location and altitude. Nights in Sofia are at a cold 11.1°C (52°F) at the beginning of June, but daytime highs scale a warm 26.7°C (80.1°F) by the month-end. Weather in June »

July is the sunniest and hottest month of the year in Bulgaria. Sofia registers at least 9.5 hours of sunshine during the 15-hour days. The average daytime highs scale highs up to 31.1°C (88°F) in the south and 28.3°C (82.9°F) in the north. Weather in July »

August is hot and sunny in Bulgaria, with the average high temperatures in the 25°C (77°F) to 31.1°C (88°F) range. Nights are mild in the zone of 12.2°C (54°F) to 18.9°C (66°F) in much of the country. The bright sunshine registers for at least 9 hours and the daylight lasts up to 14.5 hours. Weather in August »

September is sunny and warm in the beautiful autumn season in Bulgaria. The landscape becomes colorful by the third week of the month in the north, and the colors gradually travel to the south. The average high temperatures are in the warm range of 21.7°C (71.1°F) to 27.8°C (82°F), with 7.5 hours of sunshine every day. Weather in September »

October is a colorful month, with mild weather in Bulgaria. The peak fall foliage showcases brilliant hues all over the landscape during the 11-hour days. The daily sunshine lasts for an average of 5.5 hours, as the daylight fades gradually. Weather in October »

November ends the autumn in Bulgaria, with average temperatures in the -1.7°C (28.9°F) to 13.3°C (55.9°F) range. The 10-hour warm days end in early sunset by 5 p.m. and cold nights. The average temperatures in Sofia register in the cold -1.7°C (28.9°F) to 13.3°C (55.9°F) range, with many nights below freezing. Weather in November »

December is the beginning of the cold winter in Bulgaria. The average temperatures remain above 4.4°C (39.9°F) during the day but drop significantly below freezing at night. Ruse records average temperatures in the zone of -2.8°C (27°F) to 6.7°C (44.1°F). Weather in December »