The distribution of rainfall over time significantly affects the water resources of a river or watershed. The unequal distribution of rainfall intensities increases the frequency and intensity of extreme environmental events, often triggered by droughts or floods. Using the Google Earth Engine (GEE), this study uniquely integrates two decades of climate data to reveal shifting rainfall-vegetation dynamics and increasing thermal extremes in southern Indian states from 2003 to 2023, utilizing Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) and Moderate Resolution Imaging Spectroradiometer (MODIS). Along with the analysis of yearly accumulated rainfall, the lowest rainfall, ranging from 800 to 900 mm, was recorded in 2004, 2009, 2011, 2014, and 2015. Similarly, monthly and daily thermal variations in May and June usually reach peak temperatures of 44-46 degrees C. Since 2014, there has been a noticeable increase in temperature compared to other years. The Enhanced Vegetation Index (EVI) values for February to June from 2018 to 2023 range from 0.22 to 0.33; from September to November, they range from 0.35 to 0.45. The EVI-rainfall relation decreased, with recorded R2 values of 0.78 in 2003 and 0.70 in 2023, affecting the rainfall variance in this region, along with other variables, including heat fluctuation and dryness. Additionally, a negative correlation was found between the Standardized Precipitation Evapotranspiration Index (SPEI) anomaly and SPEI-LST (Land Surface Temperature). This research indicates that areas must be adequately safeguarded against significant natural disasters and the consequences of climate change to mitigate agricultural productivity loss, flood risk, and food scarcity.