A 4-km long-term (1952–2025) daily hydrometeorological dataset for the western United States

This study introduces the Western U.S. High-resolution Long-term Dataset for HydroMeteorology (WHiLD-HM), a 4-km, 74-year spatiotemporally continuous daily dataset spanning 1952-2025 for the western United States (WUS). WHiLD-HM is generated by driving the Noah-MP version 5.0 land surface model with observed precipitation, surface air temperature, downward shortwave radiation, and specific humidity, along with dynamically downscaled reanalysis-based surface air pressure, downward longwave radiation, and wind speed. The dataset encompasses key hydrometeorological variables, including surface energy and water fluxes. Cross-comparisons with observational datasets demonstrate the high temporal and spatial accuracy of WHiLD-HM. Case studies illustrate WHiLD-HM's ability to capture long-term drying trends in WUS, as well as extreme drought and pluvial conditions. By extending coverage beyond the satellite era, WHiLD-HM enables high-resolution analyses of daily to multidecadal hydroclimatic variability and trends, as well as extremes, providing crucial insights for water resources and food security management and ecohydrological monitoring.