This visualization presents six weeks of daily COVID-19 case counts for three Ohio counties—Butler, Hamilton, and Montgomery—as separate heatmaps stacked vertically. Each chart maps week on the y-axis and day of week on the x-axis, with cell color intensity reflecting case volume via a blue sequential scale. Hovering reveals the exact date and case number. The code uses D3.js v6 to load CSV data, build band scales, and render SVG rectangles with tooltip interactions.