A hydrometeor classification was performed for a squall line during the WET AMC and TRMM LBA field experiment campaign in Rondônia, Brazil. The S-POL measurements were used with two types of hydrometeor classification procedures. Namely, the one developed by Straka et al. (2000) which is based on extensive observational and modeling polarimetric studies; hydrometeors are classified according to arbitrary boundaries in a multidimensional polarimetric space. The second one was developed by Vivekanandan et al. (1999) and uses a fuzzy logic algorithm. Preliminary results are consistent with expected vertical microphysical structures and cloud types below and above the bright band, respectively. Data sets from the CITATION aircraft were also used to verify the two procedures.