<p>Specific inundation patterns and salinity levels primarily influence the distribution of fringe mangrove species. A comprehensive analysis of hydrological variability in four semiarid coastal systems located in northwestern Mexico was conducted by deploying water-level loggers over the course of one year. Additionally, environmental data on air temperature, rainfall, and surface salinity were gathered by means of the ERA 5-Land platform and spaceborne sensors. The coastal systems under study consist of two rivers with highly dynamic coastal geomorphology at their mouths and two coastal lagoons that maintain permanent connections to the ocean. The aim of this study was to investigate the effects of water level and environmental variables on the distribution of the two dominant fringe mangrove species from semiarid regions of the eastern Pacific coast. Results indicate that white mangroves (<i>Laguncularia racemosa</i>) thrive predominantly in the fringe section of the two rivers due to seasonal variations in their ephemeral connection with the ocean and low surface salinity. On the other hand, the dominance of red mangroves (<i>Rhizophora mangle</i>) along the edges of the two coastal lagoons is attributed to the strong tidal influence, as revealed by the wavelet coherence analysis and the presence of higher surface salinity. This study enhances our understanding of the distribution patterns of the two dominant fringe-type mangrove species in semiarid systems with marked seasonal fluctuations of freshwater for future rehabilitation endeavors.</p>