The month of May 2024 was the second coldest in the last 20 years, according to a National Institute of Meteorology and Hydrology. Average monthly temperatures were between 12 and 18 degrees and have a deviation from the monthly norm between minus 2.5 and 0 degrees, Nova TV reported.
The highest measured temperature was 31.6 degrees on May 22 in Parvomai. The lowest minimum temperature at a station in a populated place was 1 degree on May 14 in Malko Tarnovo, and the lowest temperature measured on a mountain peak was minus 9.7 degrees on the Musala peak on May 11. In Sofia, the highest measured temperature was 25.2 degrees on May 7, and the lowest – 4.4 degrees on May 12.
In most of the country, the monthly amounts of precipitation are between 50 and 150% of the climatic norm. Amounts below 50% are found only in some places in Eastern Bulgaria (Elhovo, 43%), and above 150% – in Western and Central Bulgaria (Ivaylovgrad, 223%). This is the rainiest month of May since 2017. The largest measured 24-hour amount of precipitation was 75 mm of rain and hail in the village of Ostrov, reg. Vratsa, on May 9.
During many days of the month, hail was recorded in different parts of the country. The largest number of stations with recorded precipitation from hail occurred on 9, 23 and 30 May (a process realized for the 24-hour period from 8.30 a.m. on the previous day to 8.30 a.m. on the indicated date).
During most days of the first ten days of May, the baric field over the country was cyclonic. Around May 3–4 and 8–9, cold atmospheric fronts passed and there were precipitation and thunderstorms in many places, and in some of them the phenomena were intense, and the precipitation – significant in quantity. A relative stabilization of the atmosphere occurs in the middle of the period, when a baric ridge is temporarily built over the country.
On May 8, rain and hail fell – 38 mm (l/sq.m) in less than 3 hours flooded the streets in the central part of Pleven, trolleybus transport was temporarily stopped. On the same day and on the night of May 9, as a result of significant amounts of rain, the Deleinska river overflowed its bed and flooded the village of Deleina, reg. Vidin.
The rising waters flooded some of the houses in the village. The power supply is temporarily interrupted. The 24-hour amount of precipitation in Vidin is 46.4 mm (l/sq.m), in Novo Selo – 53.2 mm (l/sq.m).
At the beginning of the second ten days, the weather was sunny. Daytime temperatures rise, but morning temperatures are low. On most of the remaining days of the period, thundershowers were recorded at many places in the country. The highest maximum temperatures were between 25 and 30 degrees.
At the beginning of the third ten-day period, there is a relative stabilization of the atmosphere and an increase in temperatures. On May 22, under the influence of a passing cold atmospheric front, the air mass becomes labile, powerful cumulonimbus clouds develop, short-term intense precipitation with thunderstorms and hail falls. On that day, a powerful thunderstorm, accompanied by strong wind, rain and hail, flooded the eastern neighborhoods of Sofia. The rain that fell in 50 minutes was 49.2 mm (l/sq.m), and for the day – 58 mm (l/sq.m).