Drought episodes pose severe dangers to agricultural productivity and disrupt global socio-economic situations. Climate change and global warming are predicted to intensify drought risks and their impacts on natural resources and agricultural systems. A study was conducted at the Agro-Climate Research Centre, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India, to monitor and assess the multi-scale drought dynamics across different agro-climatic zones of Tamil Nadu during 1991–2024. In this study, the standardised precipitation index (SPI) was combined with multi-source weighted ensemble precipitation (MSWEP) data, the normalised difference vegetation index (NDVI) and vegetation condition index (VCI) anomalies derived from Moderate Resolution Imaging Spectroradiometer (MODIS) cropland images from 2002–24. The lagged Pearson correlation was used to quantify the relationship between aridity and vegetation in 38 districts and seven agro-climatic zones (ACZs). Standardised precipitation index classified 2002, 2003, 2013 and 2016 as state-wide drought years. Deficiencies in the Northeast monsoon (NEM) led to far more severe agricultural stress than deficiencies in the Southwest monsoon (SWM). The Southern and Northeastern zones suffered disproportionate damage. Crop canopies responded to moisture loss instantaneously, with 95 % of ideal responses showing a zero-month lag. The NDVI anomaly and NDVI (r = 0.46–0.49) were better than the raw NDVI (r ≈ 0.29) compared with the short- to medium-term SPI (SPI-3 and SPI-6). The link was strongest in the interior agricultural areas (mean r = 0.48), but the crop response to vegetative indices was minimised across the irrigated coastal regions. This research finally provides farmers and policymakers with useful zone-specific early warning information for efficient deficit irrigation management, planting window adjustments and the deployment of drought-tolerant crop types to further improve crop productivity.