Climate change is manifested by a modification in the frequency and intensity of extreme climatic phenomena that can cause significant damage to human activities and ecosystems. The objective of this study is to carry out a comparative analysis of the observed evolution of hydroclimatic extremes between the cities of Niamtougou (Togo) and Zinder (Niger) from 1980 to 2020. Daily data on rainfall and temperature (minimum and maximum) were used to calculate six (06) extreme rainfall indices and six (06) extreme temperature indices. Furthermore, the non-parametric Man-Kendhal test and Sen’s slope were applied to estimate trends in hydroclimatic extreme indices. The results indicate an increase in all extreme rainfall indices in both Niamtougou and Zinder. As for the indices relating to extreme temperatures, only the frequency of cool days and the frequency of cool nights show a negative trend in these two cities. These results are important for better management of climate risks in the study areas.
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