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
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
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.
Weather in January
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. Stara Zagora registers average temperatures between -5°C (23°F) to 4.4°C (39.9°F), while Plovdiv is between -2.8°C (27°F) to 6.1°C (43°F). Mount Musala receives 762mm (30") to 1016mm (40") of snow and is icy between -12.8°C (9°F) to -7.2°C (19°F). Frost and fog dominate the mountains and valleys. The sunlight lasts for less than 3 hours during a maximum of 10 hours of daylight. Winter precipitation is a mix of rain and ice to the tune of 25.4mm (1") to 50.8mm (2"). The relative humidity is in the comfortable range of 55% to 60%. However, the skies are overcast for at least 50% of the time. Visitors and snow lovers need warm winter coats, gloves, and caps in Bulgaria in January.
Weather in February
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. The average temperatures in Varna on the east coast range between -1.7°C (28.9°F) to 8.3°C (46.9°F), with the seawaters at a cold 7.2°C (45°F). The sea coast sees a predominantly northern wind with average hourly speeds of 18.7km/h (11.6mph). Winter does not bring much more than 25.4mm (1") to 38.1mm (1.5") of icy rain. Kudrzhali in the south-central region has relatively mild winters due to the Mediterranean influence. The daylight improves to 11 hours in February, and the sunlight exceeds 4 hours despite a minimum 55% cloud cover. February is cold in Bulgaria and often brings snowstorms at high elevations.
Weather in March
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. Snowfall is little on the plains but ample on the high mountain slopes. The average temperatures in Sofia are in the cold to the mild range of -2.2°C (28°F) to 13.9°C (57°F). Ihtiman ranges between -2.2°C (28°F) to 13.3°C (55.9°F), while Stara Zagora is between 1.1°C (34°F) to 11.7°C (53.1°F). The moderate sunshine lasts for 5 hours during the 12-hour days. The earliest sunrise in March occurs at 6 a.m., and the latest sunset is at 7.45 p.m. March is the windiest month of the year in many places, with average hourly speeds of 11.3km/h (7mph) to 14.5km/h (9mph). Warm jackets serve well after sunset in the spring season. The weather gradually warms up with each passing day in March in Bulgaria.
Weather in April
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. Plovdiv and Stara Zagora on the Thracian Plain are warm between 5°C (41°F) to 20.6°C (69.1°F). The daily sunshine lasts for 6 hours in Sofia, which registers mild to warm temperatures between 5°C (41°F) and 16.1°C (61°F). A beach holiday is cheap in the spring season as fewer tourists visit the eastern shores, with seawater temperatures at a cold 10°C (50°F). Wind speeds are in the 12.9km/h (8mph) to 16.1km/h (10mph) range in Varna, with a predominantly westerly direction. The precipitation registers between a moderate 38.1mm (1.5") to 50.8mm (2") in most regions, with snow confined to the upper mountain slopes. The relative humidity is between 55% and 60%, and the skies are clear for 60% of the time. Expect the conditions to brighten up by the end of April in Bulgaria.
Weather in May
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. The warm sunshine lasts for 7.5 hours during the long, 14.5-hour days. The precipitation begins to pick up, especially in the north, where it registers between 63.5mm (2.5") to 76.2mm (3"). Afternoon thunderstorms are common in the second half of May. Expect a fair number of visitors on the Black Sea shores, at Varna, with seawaters above 15.6°C (60.1°F). The southern half is bright, with clear skies for 64% of the time in Plovdiv. The average monthly humidity rises above 75%, with a relevant drop in wind speeds in much of the country. Pack long pants and a light jacket for the evenings. Expect warm days and cold nights in May in Bulgaria.
Weather in June
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. The Black Sea coast sees high temperatures between 23.3°C (73.9°F) to 26.1°C (79°F) and lows between 13.3°C (55.9°F) to 23.3°C (73.9°F). The seawaters reach a warm 22.2°C (72°F) and attract hordes of tourists to the beautiful beaches. June 20 is the longest day in Varna at 15 hours and 23 minutes, with 8.5 hours of brilliant sunshine. The average hourly wind speeds clock at 12.9km/h (8mph) to provide a pleasant atmosphere. The northern cities register 50.8mm (2") to 63.5mm (2.5") of precipitation, while the southern record below 38.1mm (1.5"). The brightest days in June have clear skies for 83% of the time. Expect afternoon thunderstorms on a trip to the mountains. June is a wonderful time to visit Bulgaria.
Weather in July
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. Night temperatures are usually mild and register in the 13.9°C (57°F) to 17.8°C (64°F). Varna ranges between a warm 17.2°C (63°F) to 30°C (86°F), with average seawater temperatures at a warm 75°that attract crowds. Mount Musala has cold nights at 2.8°C (37°F) and warm days at 10°C (50°F). Tourists have plenty of time for outdoor explorations, with sunset past 9 p.m. July 20 is the brightest day in Sofia with the skies clear for 88% of the time. The relative humidity is between 60% and 75%, and the rainfall is above 50.8mm (2"). The average hourly wind speeds are between 8km/h (5mph) to 9.7km/h (6mph) on the plains. Expect hot afternoons in the interior areas of Bulgaria in July.
Weather in August
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. The skies remain clear for 88% of the time in the plains. The precipitation sees a decline to register an average of 38.1mm (1.5") in the month. The relative humidity is slightly high between 65% and 70%, and the days are sultry in a few areas. In the hot season, light summer clothing, t-shirts, and sweatshirts in the day, and long pants in the evening are suitable. An umbrella or a light jacket is useful during rain showers. The average seawater temperatures at 25°C (77°F) in August make it an excellent time to swim and sunbathe on the beaches. August is the perfect time to explore the mountain peaks in Bulgaria.
Weather in September
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. Nights average between 8.3°C (46.9°F) and 15°C (59°F) in most parts and rarely fall below 7.2°C (45°F). The 12.5-hour days see an increase in cloudy skies from 20% to 37% of the time by the end of the month. The rainfall is a modest 25.4mm (1") to 38.1mm (1.5"), and the conditions are mostly dry and sunny. The seawaters are still warm at an average of 22.2°C (72°F), and the average hourly wind speeds register up to 16.1km/h (10mph) on the coasts. The relative humidity is between 55% and 75%, so expect humid periods during the day. The second half of September offers excellent weather for a visit to Bulgaria.
Weather in October
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. October is wetter in the south compared to the north but does not yield more than 50.8mm (2") of precipitation. The first half of October is warm and bright, with clear skies for 62% of the time. Mount Musala reports the first freezing nights of the season, with average temperatures between -2.8°C (27°F) to 2.8°C (37°F). Sofia average temperatures vary between 2.2°C (36°F) to 20.6°C (69.1°F) as the cold increases in the second half of the month. Expect sunny periods followed by cold ones, and carry a jacket during evenings on outdoor excursions. The coastal regions have bright sunshine, with average seawater temperatures at 17.8°C (64°F). The high mountains see the first snowfall of the season. October gradually becomes cold in the second half in Bulgaria.
Weather in November
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. Most of the country receives light snowfall by the second half of the month, as the trees begin to show bar limbs. The precipitation increases to 50.8mm (2") by the beginning of the winter. The skies are cloudy for 45% of the time, and the weak sunshine lasts only for 3.5 hours. The coasts see fewer crowds, with average seawater temperatures at a cold 13.9°C (57°F). Varna sees cold nights between 2.2°C (36°F) to 6.1°C (43°F) on the Black Sea coast. Wind speeds increase above 16.1km/h (10mph) as the humidity registers between 55% and 65%. November is a time to wear warm clothes, such as jackets and sweaters, in Bulgaria.
Weather in December
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). Sofia and Ihtiman register in the cold range of -5°C (23°F) to 6.1°C (43°F), with a few nights below -10°C (14°F). Plovdiv and Varna are slightly mild in the -1.1°C (30°F) to 9.4°C (48.9°F) and even see a few days at 15.6°C (60.1°F). Cloud cover remains between 50% and 60%, and the first week of December is often the cloudiest period of the year. The precipitation is low in the range of 25.4mm (1") to 38.1mm (1.5"). Snowfall is moderate in the plains but abundant in the high mountains. The sunlight is weak and hardly lasts for 2 hours every day. December 21 is the shortest day of the year, with only 9 hours of daylight. The average hourly wind speeds are in the mild range of 8km/h (5mph) to 9.7km/h (6mph), with a predominantly westerly direction. The skiing season begins in Bulgaria in December.