In this study, we analyze the temporal dynamics of monthly rainfall series recorded at 133 gauging stations in the state of Pernambuco, northeastern Brazil, from 1962 to 2012. The study region spans from the Atlantic coast (Zona da Mata) where the climate is tropical humid, to the deep inland region Sert & atilde;o with a semiarid climate. Between Zona da Mata and Sert & atilde;o, there is a transition region Agreste with a sub-humid climate. We use the Fisher-Shannon method, which simultaneously quantifies the disorder and structural organization of temporal series through the calculation of Shannon entropy power \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{N}_{X}$$\end{document} and Fisher information measure \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{I}_{X}$$\end{document}, respectively, defining their position in the Fisher-Shannon plane (FS). Results show that rainfall series from different climate zones occupy distinct regions in the FS plane: stations in the Zona da Mata display higher entropy and lower Fisher information (higher disorder, lower structural organization), while those in the Sert & atilde;o show lower entropy and higher Fisher information (lower disorder, higher organization). In the Agreste, higher-altitude stations tend to exhibit higher entropy values. Spatial patterns reveal a clear west-east gradient: increasing Shannon entropy power and decreasing Fisher information. For both FS quantifiers as well as Fisher Shannon complexity \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{C}_{X}=\:{N}_{X}{I}_{X}$$\end{document}, we found statistically significant differences between all regions. The k-means clustering method, based on \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{C}_{X},\:$$\end{document}station longitude, and elevation, classifies 133 stations in three clusters that reflect the diversity of rainfall regime in Northeast Brazil. Our findings indicate that the Fisher-Shannon method has the potential to discriminate among different climatic conditions.