Multilingual Community Visualizations (MCV): A GIS Dashboard for Linguistic Research and NWS Operations

Liam E. Llewellyn , Joseph E. Trujillo-Falcón , Todd D. Fagin, Samuel T. Halvorson, Monica L. Bozeman, Ennis Shabab

The NWS is actively expanding its multilingual outreach to better serve the 68.8 million U.S. individuals who speak a language other than English at home. Among these, 26.3 million individuals with Limited English Proficiency (LEP) are of particular concern, as they often rely entirely on translated forecasts to make life-saving decisions. Yet identifying where these populations are concentrated has remained a persistent challenge for researchers and forecasters alike. To address this issue, we developed the Multilingual Community Visualizations (MCV) dashboard, a geospatial tool that maps language diversity of LEP populations across all 122 NWS Weather Forecast Offices. Using 2019 American Community Survey (ACS) 5-year estimates, we implemented a detailed data processing workflow, including dasymetric mapping to resolve Modifiable Areal Unit Problems where County Warning Area (CWA) boundaries do not align with Census geography. The dashboard, developed in ArcGIS Online, provides interactive, CWA-specific insights through data visualizations, percentage maps, and dot density layers. Since its release, MCV has supported language services across the NWS and informed targeted research and operations in vulnerable LEP communities. It serves as both a research tool and operational asset, demonstrating the power of GIS-integrated demographic analysis. We conclude with a discussion of future improvements, including automating the workflow, integrating updated ACS data, and incorporating broader demographic indicators. The MCV dashboard represents a scalable model for leveraging demographic data to advance targeted, data-driven public safety communication.