Precipitable Water Vapor (PWV) is essential for weather forecasting, especially for extreme events like floods and droughts. While traditional methods are accurate but limited in coverage, GNSS technology offers a cost-effective, continuous solution using real-time Zenith Total Delay (ZTD) measurements. This study presents the development of an automated PWV mapping system utilizing ZTD data from the HII GNSMART network, combined with meteorological data. The system integrates GNSS-based atmospheric observations with meteorological parameters, including surface temperature, and pressure, to enhance the accuracy of PWV estimation. The system enhances the accuracy of PWV estimations. The data processing pipeline is fully automated, delivering near-real-time PWV updates on an hourly basis, ensuring timely and reliable weather analysis. The research results indicate that validation confirms a correlation between Zenith Total Delay (ZTD) and short-term weather changes. When the ZTD value ranges between 2.2–2.5 and increases over the next 2 to 3 h, it demonstrates the effectiveness of GNSS in enhancing short-term weather forecasts.