摘要：The increased frequency of the climatic hazards requires more and more detailed studies on this issue. Thus, the present paper aims at identifying the critical precipitation spells for the Transylvanian Depression area. In this respect, statistical data from 1971-2000, recorded in 10 weather stations (Cluj-Napoca, Blaj, Sebeş, Tg. Mureş, Dumbrăveni, Sibiu, Făgăraş, Dej, Bistriţa, Odorheiu Secuiesc) were used. The main conclusions are the following: in the analyzed region, most of the days within the year (110...131 days) have a frequency of precipitation occurrence between 30...40 %; at the weather stations protected by the Apuseni Mountains and by the Southern Carpathians (Blaj, Sebeş, Sibiu), the “precipitation shadow” is felt and so, the number of rainy days with an occurrence frequency higher than 40% decreases if compared to the other analyzed weather stations within the studied area; the length of critical precipitations spells, common to most of the analyzed weather stations, ranges between one and 21 running days (for an occurrence frequency higher than 40%) and between one and 6 running days (with an occurrence frequency higher than 50%), respectively; critical precipitation spells, common for the entire region, are missing in March, while in August and October have a very low frequency (1-2 days).
