This article analyzes news content related to Chiang Mai Province published between December 23, 2025, and January 5, 2026. The selected period covers seven days prior to and seven days during the implementation of the “Seven Dangerous Days” road safety campaign organized by the Department of Disaster Prevention and Mitigation (DDPM) and the Road Safety Directing Center (RSDC), conducted under the campaign titled “Drive Safely, Reduce Speed, Reduce Accidents.” The news posts were disseminated in English via the Facebook Group (FBG) Chiang Mai News. The study aims to: (1) analyze types of metonymy used in headlines using the framework of Lakoff and Johnson; (2) categorize key issues concerning Chiang Mai that were constructed as agenda-setting topics in a local English-language news platform targeting foreign audiences in terms of frequency and percentage; and (3) analyzes the issues that attract readers’ attention using Uses and Gratifications Theory, based on the number of “likes” received. The findings revealed that the most frequently occurring types of metonymy in highly engaged headlines were institution for people responsible (50.04%), controller for controlled (28.59%), and place for the institution (14.29%), respectively. Regarding agenda-setting patterns, the most emphasized issue category was tourism/festivals/events (26.47%), followed by accidents/road safety (18.62%), government policies/official announcements (9.80%), and crime/law enforcement (8.82%). In terms of Uses and Gratifications Theory, the analysis indicated that readers primarily used the platform to fulfill four major needs: entertainment and emotional enjoyment, practical information for daily life, safety awareness, and a sense of community belonging. Moreover, it was found that headlines employing metonymy in these news agendas are associated with higher levels of reader engagement, as reflected in the number of “likes.” This is because metonymy links the news content to familiar social contexts and interests, enabling readers to grasp the key message more quickly. Metonymy thus functions as both a linguistic and cognitive mechanism that supports the process of agenda setting and enhances reader engagement in the context of social media.