Summer 2026 turned out cooler and wetter on average across Bulgaria than the last two years. That's the finding of the National Institute of Meteorology and Hydrology, based on data from weather stations, media report.
Still, average seasonal temperatures stayed above the usual levels for the period. The highest temperature recorded all summer was 40.5C, measured on 21 August in the village of Novachene, near Pleven. The lowest minimum temperature at a station in a populated area was 4.5C, recorded on 16 August in Samokov. But the season's absolute low came at the peak of Musala, where the thermometer showed minus 2.6C on 23 July.
Rainfall varied sharply by region. Seasonal totals ranged from 34% of the usual amount in Sungurlare to 196% in the village of Goren Chiflik, near Varna. That village also recorded the country's highest seasonal rainfall total, at 275mm. On 23 July, the same village also saw the summer's biggest 24-hour rainfall, at 107.1mm. In Sofia, the heaviest 24-hour rainfall came on 2 July, when 31.1mm of rain and hail fell in a day.
The institute also laid out how the season unfolded weather-wise. In the first half of June, air pressure at ground level was higher than usual on most days. Higher up, a trough moved through as a ridge built from the south-southeast. The weather stayed mostly sunny, but storm clouds built up almost everywhere by afternoon, bringing thunderstorms, short bursts of rain, and in places hail and strong gusts of wind. These were most widespread and intense on 2, 4, 11 and 12 June. In the mornings, frequent rain and high humidity brought fog and poor visibility in some areas. Temperatures stayed close to normal until the last two days of June, when the first heatwave hit and highs in some places reached 38-39C.
The sea along Bulgaria's coast also saw several sharp swings during the season. In the second ten days of June, north of Varna, the water cooled quickly twice. On 12 June and into the night of the 13th, a moderate wind from the west-northwest pushed surface water out to sea. The temperature dropped near Shabla by about 3 degrees, from 17.5C to 14.3C, and near Varna by nearly 8 degrees, from 22.2C to 14.5C. On the night of 15-16 June, the water near Shabla dropped again, this time because of a south wind, falling from 19.6C to 16.3C.
Similar sharp swings happened again in July. On the night of 8-9 July, the wind briefly turned northwest and the water near Shabla cooled by about 5 degrees, from 22.5C to 17C. The next night, going into 10 July, brought another, smaller drop of about 2 degrees, from 23.6C to 21.8C. Between 10 and 14 July, sea temperatures fell all along the coast, most sharply near Ahtopol, where the water was just 19.6C on the morning of 13 July. On 19 and 27 July, a moderate south wind brought more sharp drops near Shabla, down to 19-20C. On the morning of 25 July, the water in Varna Bay briefly dropped by almost 5 degrees.
July also brought several cold fronts. At the start of the month, and again at the end of the second and start of the third ten-day period, powerful storms broke out in many places, with heavy rain, hail and strong wind. On 24 July, it even snowed on the highest peaks of Rila and Pirin.
The August heat arrived between 20 and 22 August, when a ridge of high pressure and heat over the country brought the highest temperatures of the whole summer, up to and above 40C. On 24 August, the wind direction changed as air began moving in from the west, stirring up the Macedonian low, and the air over western and central Bulgaria turned unsettled. Storm clouds built up there, bringing short bursts of rain, thunderstorms and hail, while parts of southwestern and central-northern Bulgaria saw heavy, sustained rain.
The strong storms and heavy rain and hail were the defining feature of summer 2026, the institute says in its report. In places, they caused local flooding. Homes and yards were flooded, infrastructure was damaged, and power and water were briefly cut in the affected areas. The Kotel-Omurtag and Peshtera-Batak roads were closed for a time. Institute data show that 24-hour rainfall in these areas often reached 50-100% of the usual amount for a whole month. In June and July, flooding hit the Blagoevgrad, Varna, Vidin, Plovdiv, Yambol and Sofia city regions. In August, rivers and streams overflowed, and a state of emergency was declared in the Simitli, Batak and Peshtera municipalities. In Peshtera, a person went missing in the river on 24 August.
In late July and through August, southern Bulgaria also saw several major fires, which the institute blames on human carelessness or farm work. Close to 20,000 decares of farmland and forest burned, half of it in a single fire in the Haskovo region that swept through the villages of Dinevo, Lyubenovo, Malevo and Krivo Pole. Besides carelessness, some fires during the season were sparked by lightning. On 4 June, during a thunderstorm near Kresna, lightning struck a construction worker and injured two others. In late July, lightning strikes again caused several fires in the south of the country.