Drought is a complex natural hazard connected with the lack of water. In terms of the lack of water two types of drought can be identified, namely meteorological and hydrological drought. Recently, an economic and sociological aspect have been increasingly attributed to drought. leading to the agricultural drought. With the increasing trend of drought occurrences also the cases in which meteorological drought turns into agricultural and later into hydrological drought increase. Both agricultural and hydrological droughts have negative economic consequences, such as crop reductions and limiting water use.. In the light of the above, exploring the possibility of drought forecasting seems necessary, since a good alarm system, warning and using restraining precautions could significantly reduce the negative effects of drought events.
In order to establish the possibility of forecasting drought events, we have linked drought and hydrological indexes; SPI (Standard Precipitation Index), SSI (Standard Streamflow Index), NDVI (Normalized Drought Vegetation Index); SWI (Soil Water Index), SWD (Soil Water Deficit), with measured variables of water balance in upper soil VT (Soil Water), VB (Water Balance), AVB (Agricultural Water Balance).
We have shown that considered drought indexes have high correlation coefficients among each other. The importance of covering the area with a sufficient number of meteorological and hydrological stations for monitoring the water balance and determining the relevant basin n-monthly SPI was demonstrated.. When examining the connection of remotely sensed indices with locally measured soil water balance variables, typical patterns of sequences and time delays of the variables under consideration are revealed.. From the given findings, we were able to propose scheme to start observing and evaluating the general drought development at the sites under consideration.