31:T448,newMap = htl.html`

${viewof legend}

${viewof map}

${viewof logo}

`32:Ta45,viewof map = { let tooltip = d3 .select("body") .append("div") .attr("class", "tooltip") .style("position", "absolute") .style("z-index", "10") .style("visibility", "hidden") .style("padding", "5px") .style("opacity", 0.9) .style("background", "white") .style("border", "2px solid") .style("border-radius", "2px") .style("pointer-radius", "none"); const div = d3.create("div"); const filtered = counties.features.filter((d) => d.properties.STATE !== "AK" && d.properties.STATE !== "HI"); function direction(temp) { if (temp >= 1) { return "has warmed by"; } else if (temp <= -1) { return "has cooled by"; } else { return "has remained fairly constant, warming by just "; } } // we create an SVG with the width and height specified const svg = div.append('svg') .attr('max-width', "100%") .attr('height', 600) .attr("viewBox", [0, 0, 1000, 600]); const countyGeogs = svg .append("g") .selectAll("path") .data(filtered) .join("path") // This line renders our data .attr("fill", (d) => getColor(d.properties.CHANGE_F)) .style("stroke", "black") .style("stroke-width", 0.25) .attr("d", path); countyGeogs .on("mouseover", function (e, d) { let thisDiv = d3.select(this).data()[0]; if (thisDiv !== mutable thisDiv) mutable thisDiv = thisDiv; d3.select(this).style("stroke-width", 2).style("stroke", "white"); const message = direction(thisDiv.properties.CHANGE_F); tooltip.style("visibility", "visible").html(`The average winter temperature in ${ thisDiv.properties.COUNTY}, ${thisDiv.properties.STATE} ${message} ${+thisDiv.properties.CHANGE_F}°F since 1970.`); }) .on("mousemove", function (e, d) { return tooltip .style("top", e.pageY - 10 + "px") .style("left", e.pageX + 10 + "px"); }) .on("mouseout", function (e, d) { if (mutable thisDiv) mutable thisDiv = null; d3.select(this).style("stroke-width", 0.15).style("stroke", "black"); tooltip.style("visibility", "hidden"); }); // this part renders the state borders over top of our counties svg .append("path") .datum(statesMesh) .attr("fill", "none") .attr("stroke", "black") .attr("stroke-width", 1) .attr("stroke-linejoin", "round") .attr("d", path); // we need to return a DOM element. // the .node() function returns the DOM element corresponding to the d3 selection. return div.node(); }33:Ta27,34:[{"id":"1694ac815c16d029996a80a20abcc7b6d6bc0d4b829f4e8fe6185618a218e2719e48d748eef22fbec237b4321105c55405e85454f86b9c7e79ea4ec673ac53b0","href":"https://static.observableusercontent.com/files/1694ac815c16d029996a80a20abcc7b6d6bc0d4b829f4e8fe6185618a218e2719e48d748eef22fbec237b4321105c55405e85454f86b9c7e79ea4ec673ac53b0","name":"2025WinterPackage_AvgT_Counties.csv","type":"text/csv","lastModified":1762104356209.873,"size":90123},{"id":"9877f77996aac1ac7a0f4f5a5fa7c95ab99bddbb447857cb87d4db2e856a80dc8c10f46b4f2093680bd102e31e4c534f2e9aefab12ee4601b410bc93145f395a","href":"https://static.observableusercontent.com/files/9877f77996aac1ac7a0f4f5a5fa7c95ab99bddbb447857cb87d4db2e856a80dc8c10f46b4f2093680bd102e31e4c534f2e9aefab12ee4601b410bc93145f395a","name":"2025-winter-package.geojson","type":"application/geo+json","lastModified":1762103716618.154,"size":29486931},{"id":"5a9fadd5c85c0c14f9849886a66dbd03ed67662ead98114cbe633072026e41eec8c0d8ee22bd3c3b0bffb441bf8e8b1964c6861973c9dc3f5f160324feead694","href":"https://static.observableusercontent.com/files/5a9fadd5c85c0c14f9849886a66dbd03ed67662ead98114cbe633072026e41eec8c0d8ee22bd3c3b0bffb441bf8e8b1964c6861973c9dc3f5f160324feead694","name":"CC_LongLogo.png","type":"image/png","lastModified":1762103472941.551,"size":199924}] 2f:{"title":"Climate Matters: 2025 Winter Package","cells":[{"id":189,"value":"# Climate Matters: 2025 Winter Package","pinned":false,"hidden":false,"mode":"md"},{"id":0,"value":"

Change in Average Winter Temperature (°F) by County, 1970-2025

","pinned":false,"hidden":false,"mode":"html"},{"id":14,"value":"Meteorological winter, which starts December 1, is the fastest-warming season for most of the U.S. — affecting snowfall, water supplies, winter sports, spring allergies, summer fruits, and more.\n\nThe map below shows how much average winter temperatures have changed in counties across the contiguous U.S. from 1970-2025. Read more about the impacts of increasing winter warmth in Climate Central's 2025 Winter Package.","pinned":false,"hidden":false,"mode":"html"},{"id":92,"value":"$31","pinned":false,"hidden":false,"mode":"ojs"},{"id":88,"value":"

Want to embed this map on another website?

${Object.assign(html`

\n","pinned":false,"hidden":false,"mode":"html"},{"id":32,"value":"

${DOM.download(\n FileAttachment(\"2025WinterPackage_AvgT_Counties.csv\").blob(),\n FileAttachment(\"2025WinterPackage_AvgT_Counties.csv\").name,\n \"Download Data\"\n)}

","pinned":false,"hidden":false,"mode":"html"},{"id":2301,"value":"---","pinned":false,"hidden":false,"mode":"md"},{"id":2287,"value":"Methodology: Monthly temperature data for counties across the contiguous United States were obtained from NOAA/NCEI's nClimDiv dataset. This data can also be accessed via NCEI's Climate at a Glance. While Connecticut has recently switched from counties to planning regions, NCEI does not yet have data for the new geographies. Until that changes, we will continue to use the county data available for Connecticut.","pinned":false,"hidden":false,"mode":"html"},{"id":125,"value":"---","pinned":false,"hidden":false,"mode":"md"},{"id":84,"value":"$32","pinned":false,"hidden":false,"mode":"ojs"},{"id":79,"value":"viewof legend = htl.html`

\n \n

${Legend(\n d3.scaleThreshold([`1°F`, `2°F`, `3°F`, `4°F`, `5°F`, `6°F+`], colors),\n {\n width: 700,\n height: 50,\n tickSize: 2,\n title: \"Change in average winter (DJF) temperature by county, 1970-2025\"\n }\n )}

`","pinned":false,"hidden":false,"mode":"ojs"},{"id":27,"value":"viewof logo = await (FileAttachment(\"CC_LongLogo.png\").image({width: 250, height:18}))","pinned":false,"hidden":false,"mode":"ojs"},{"id":65,"value":"embedCode = {\n return``\n }","pinned":false,"hidden":false,"mode":"ojs"},{"id":538,"value":"data = FileAttachment(\"2025WinterPackage_AvgT_Counties.csv\").csv({typed:true})","pinned":false,"hidden":false,"mode":"ojs"},{"id":63,"value":"colors = ['#fee5d9','#fcbba1','#fc9272','#fb6a4a','#ef3b2c','#cb181d', '#99000d']","pinned":false,"hidden":false,"mode":"ojs"},{"id":73,"value":"getColor = function(temp) {\n let x = +temp;\n if(x < 1) {\n return colors[0];\n } else if (x >= 1 & x < 2) {\n return colors[1];\n } else if (x >= 2 & x < 3) {\n return colors[2];\n } else if (x >= 3 & x < 4) {\n return colors[3];\n } else if (x >= 4 & x < 5) {\n return colors[4];\n } else if (x >= 5 & x < 6) {\n return colors[5];\n }else {\n return colors[6];\n } \n}\n ","pinned":false,"hidden":false,"mode":"ojs"},{"id":78,"value":"mutable thisDiv = null","pinned":false,"hidden":false,"mode":"ojs"},{"id":52,"value":"path = d3.geoPath().projection(projection)","pinned":false,"hidden":false,"mode":"ojs"},{"id":56,"value":"projection = d3.geoAlbersUsa()\n//.fitSize([width, height], countyShapes)\n// The default projection parameters used by most other county map examples instead of fitSize:\n.scale(1000)\n.translate([450, 350])","pinned":false,"hidden":false,"mode":"ojs"},{"id":22,"value":"counties = FileAttachment(\"2025-winter-package.geojson\").json()","pinned":false,"hidden":false,"mode":"ojs"},{"id":62,"value":"// The borders of the states are merged so we can render a single line where they would otherwise overlap\nstatesMesh = topojson.mesh(us, us.objects.states, (a, b) => a !== b)","pinned":false,"hidden":false,"mode":"ojs"},{"id":50,"value":"us = d3.json(\"https://unpkg.com/us-atlas@3/counties-10m.json\")","pinned":false,"hidden":false,"mode":"ojs"},{"id":45,"value":"import * as topojson from \"npm:topojson-client@3\";","pinned":false,"hidden":false,"mode":"js"},{"id":48,"value":"import * as d3 from \"npm:d3\";","pinned":false,"hidden":false,"mode":"js"},{"id":41,"value":"import {Legend} from \"observable:@d3/color-legend\";","pinned":false,"hidden":false,"mode":"js"},{"id":97,"value":"import {copy} from \"observable:@mbostock/copy-to-clipboard\";","pinned":false,"hidden":false,"mode":"js"},{"id":38,"value":"$33","pinned":false,"hidden":false,"mode":"html"}],"files":"$W34","stdlib":"2","titling":"auto"}