This interactive multi-series line chart visualizes daily average temperatures for New York, San Francisco, and Austin from October 2011 through April 2012. It displays three color-coded temperature trends over time, with a legend for city selection. The visualization supports zooming and panning along the time axis, and users can click legend items to toggle the visibility of individual city lines. Hovering over a legend dims non-selected series. The code uses D3 v7 with `d3.scaleTime`, `d3.line` with `d3.curveBasis`, and an SVG rendering. It loads data from a TSV file and includes animation via D3's transition and zoom APIs.