General Information Title: Characterizing the Spatial and Temporal Reliability of NASA POWER Meteorological Data: A Multi-Decadal Validation across Diverse Topographies in the US and Türkiye Principal Investigator: Hüdaverdi Gürkan, PhD (Turkish State Meteorological Service / University of Florida) Contact: hudaverdigurkan.tr@gmail.com Date of Data Collection: 1981 – 2024 (Variable by station) 1. Dataset DescriptionThis repository contains the gridded and in-situ meteorological data used to validate the NASA POWER dataset across diverse topographical regions in the United States and Türkiye. The parameters included are Maximum Temperature (Tmax), Minimum Temperature (Tmin), Solar Radiation, Relative Humidity, Wind Speed, and Precipitation. Group A & B: US In-situ and NASA POWER Data (Open Access) Files: Individual .xlsx files prefixed by state codes (e.g., FL_*.xlsx, GA_*.xlsx, WA_*.xlsx). Format: Each file corresponds to a specific weather station. The first sheet contains the ground-based in-situ observations, and the second sheet contains the corresponding NASA POWER data extracted for that specific location. Access: Publicly available for research purposes. Group C: Türkiye In-situ Data (Restricted Access) Status: Raw In-situ Data Not Included in this Repository. Source: Turkish State Meteorological Service (TSMS). Note: For the Türkiye component of this study, files in the repository contain only the NASA POWER data and station metadata. Reason for Restriction: The in-situ records for Türkiye are owned by TSMS and are protected by institutional data policies that prohibit third-party redistribution. How to Access: Researchers can request the Türkiye in-situ datasets formally through the TSMS official portal: https://mgm.gov.tr. 3. Metadata and Station ListFor the reproducibility of the study, a complete list of all 40 weather stations (including TSMS stations) with their IDs, coordinates (Latitude/Longitude), and elevations is provided in the file: Station_Metadata_List.xlsx. 4. Terms of UseIf you use this dataset or the methodology described in the associated manuscript, please cite:Gürkan, H., & Hoogenboom, G. (2026). Characterizing the Spatial and Temporal Reliability of NASA POWER Meteorological Data... Geoscience Data Journal.