Plot.plot({
y: {
grid: true,
label: "↑ Temperature (°F)"
},
marks: [
Plot.areaY(sftemp, {x: "date", y1: "low", y2: "high", fillOpacity: 0.3}),
Plot.lineY(sftemp, Plot.windowY(k, {x: "date", y: "low", stroke: "blue"})),
Plot.lineY(sftemp, Plot.windowY(k, {x: "date", y: "high", stroke: "red"}))
]
})