<p>The present study aims at modeling Iran’s intra- and extra-decade drought behaviors. To do so, 61 synoptic stations’ annual precipitation data were procured from Iran’s meteorology organization for 30&#xa0;years (1986–2015). To identify the various drought degrees’ frequencies in the studied stations, the Standardized Precipitation Index (SPI) was applied on an annual scale. Cluster analysis was utilized for regionalizing the droughts and empirical mode decomposition, as well, was applied to detecting Iran’s decennial drought behaviors. The results indicated that Iran can be divided into five different regions based on the annual SPI values’ time-series behaviors. Counting the number of times various drought classes occur in each of the aforesaid five regions, it was concluded that the northeastern region with 11 cases of drought, the southeastern region with 6 cases of drought, and the northern strip with also 6 cases of drought are respectively the regions with the highest and the lowest frequencies of drought occurrence. Severe and very severe drought occurrences were also observed in the northwestern region (2 cases) and southwestern region (1 case) with them not being detected in the other regions on a yearly basis. The results pertinent to the behavioral detection of Iran’s intra- and extra-decade drought cycles, as well, indicated that the changes in the fivefold region’s drought in Iran substantially feature intra-decade nature so a less than 10-year alternation should be expected for the droughts in Iran. Put differently, the drought return period takes less than 10&#xa0;years to occur.</p>