ABSTRACT. – The precipitation and temperature evolution in Cluj County, in June 2010. June, in the Cluj County area, has been a month of extremes, in both heat and precipitation. In this paper, the synoptic situation for June, over Europe and Romania, was analysed. The first part of June was characterized by the persistence of a hot North African ridge over the European territory. Thus, at the beginning of the month, daily maximum temperatures were close to the normal, then, gradually, the maximum temperatures increased from day to day, reaching very high values – up 34 °C by the middle of the month when the temperature-humidity index (ITU) reached and exceeded, in relatively large areas, the critical level of 80. In the second part of June, the target area was characterized by atmospheric instability. At the 500 hPa at isobaric level across the continent the presence of a trough that extends from the north-east- over the central European countries, to the south-west, between two high pressure zones- one located above the North Atlantic (Azores High) and another over the Russian Plain (Eastern European anticyclone), can be detected. The synoptic structure from the altitude characterizes a strong blockage that will favor the polar cold air penetration to the south part of the continent, and cut-off type structure positioned above the Italian Peninsula will quickly cross the Mediterranean basin to the Balkan Peninsula. The presence of the thermal blocking to the east and northeast sides of the Black Sea will cause the stationing and reactivation of the cut-off core by the end of June. Strong convective structures developed- which led to the recording of large amounts of water from showers and heavy rain, that were associated with floods and strong winds, which turned into storms with hail and lightning. For the second half of the month, a particular case dated 06/21/2010 was analyzed, the day which registered the most destructive effects of the floods. The outcome of the floods were, as reported by the Inspectorate for Emergency Situations Emergency (ISU) in Cluj County: the death of a person, the flooding of 250 homes and landslides.
Keywords: ITU, thermal convection, precipitation, floods.