In arid to semi-arid climates, monitoring drought is very complicated because of different hydrometeorology variables effect on it.ItisproposedinthispapertodevelopFuzzyIntegratedDroughtIndex(FIDI)whichcombinesmostimportanteffectivefactors indeveloping drought.At first,Variable InfiltrationCapacity(VIC) model calibratedsimulatedrunoff tooutletbasinrunoff data for years 1993–1995. Results represent high performance of model in simulating runoff of outlet basin. Then, Precipitation Anomaly Percentage Index (PAPI), actual Evapotranspiration Anomaly Percentage Index (EAPI), Runoff Anomaly Percentage Index (RAPI), and Soil Moisture Anomaly Percentage Index (SMAPI) were constructed. FIDI was compared with the PAPI, RAPI and SMAPI for the period of 1985to 2014. The results indicate that(1) the FIDI has more ability in determining start and persistence of drought event compared with PAPI, RAPI, and SMAPI; (2) in the low time scales, PAPI and SMAPI have high correlation withFIDI,and inthe highertimescales, RAPIhas the highcorrelation withFIDI;(3) spatially, the middle,west,and portion of north have higher drought risk in the Neyshabour basin.

Keywords