For the period 1961-2018 (Bilje since 1963, Portorož since 1993) we analyzed meteorological water balance on an annual scale, in vegetation period (April-September) and for summer (June-August) for meteorological locations Bilje (55 m), Celje (241 m), Godnje (320 m), Ljubljana (299 m), Murska Sobota (188 m), Novo mesto (220 m), Portorož (2 m) and Slovenj Gradec (455 m). Data for monthly precipitation and reference evapotranspiration are from archive of Slovenian Environment Agency. For all periods and stations, we calculated average, minimum, maximum and variation range for precipitation, evapotranspiration and water balance. Between the considered locations, there were large differences between precipitation, evapotranspiration and water balance patterns. On an annual scale, average water balance was positive at all stations, with the exception of Portorož, where long-term average for water balance was negative, ⠒122 mm. Average water balance in summer is positive in Ljubljana and Celje, for others stations the water deficit in the period considered ranged from ⠒17 mm in Celje to ⠒286 mm in Portorož. The average water balance in vegetation period is negative in Murska Sobota (⠒98 mm) and Portorož (⠒353 mm), for other stations is positive. However, after the year 2000 negative water balance prevails at all locations. Evapotranspiration increased relatively more during the growing season that on the annual level. On average, Portorož (815 mm) and Murska Sobota (566 mm) have the highest evapotranspiration during vegetation period. A comparison of precipitation for the periods 1961-1990 and 1991-2018 for annual, summer and vegetation period showed that, in general, the amount of precipitation in the second period decreases slightly. Evapotranspiration is higher at all stations in the second period, the largest change is in Bilje (122 mm).
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