Local Health Signal is a public information service that helps people check current health conditions in their area. It provides weekly CDC-based readings for all 50 states and 499 U.S. cities, covering flu-like illness, COVID-19, RSV, measles, and related local health context. Users can search by city or state, compare respiratory signals over time, review source weeks and methods, and explore illness-specific reports. City checks are based on statewide readings, and the site notes that weekly reports may lag behind infections.

Beyond health snapshots, Local Health Signal offers state and city overview pages, weekly updates, a near-me finder, and travel health checks. Its tap-water resources cover official water reports, lead service line checks, PFAS notes, and rental water questions for selected cities. The site also provides MMR vaccination coverage comparisons, public health guidance, common questions, and weekly roundups designed to make current information easier to understand and share. It clarifies that its data cannot diagnose illness or replace medical advice, and directs users to healthcare providers for personal guidance.