Western shifting of Extreme Rainfall Events over the different Indian River Basins in the last 119 years

India experienced more flood situations due to the increasing extreme rainfall events over the different Indian River Basins (IRBs) during the last few decades. An Extreme Value Theory (EVT) is used to examine trends of rainfall extremes over the IRBs using long-term observed high-resolution grid-based rainfall (1901-2019) of the India Meteorological Department. The analysis depicts that when generalized extreme value theory (GEV) is applied to annual maximum rainfall over IRBs, statistically significant uniform trends were not seen. The spatial variations in the annual maximum rainfall for the 10-, 30- and 100-year return levels show statistically significant increasing trends over the IRBs. The shifting trend of rainfall extremes from northeast towards the western river basins of IRBs in the last two decades and resulted in damage to life and property on the west coast. The decadal changes in average intensity of dry and wet condition at 12- months running time window reveals that the shifting and increasing pattern of the rainfall extremes events during the last decades of the 20th century (1981-2000) and current decades of the 21st century (2001-2019) over the western ghats and west-flowing river basin leads to several floods situations. This research highlights the significant increasing trend in extreme rainfall events over the IRBs, which may pose a grave risk to agriculture, human life, and predominantly on the vulnerable sections of the society.