Stacked Bar Chart

{
  "$schema": "https://vega.github.io/schema/vega-lite/v2.json",
  "data": {"url": "data/seattle-weather.csv"},
  "mark": "bar",
  "encoding": {
    "x": {
      "timeUnit": "month",
      "field": "date",
      "type": "ordinal",
      "axis": {"title": "Month of the year"}
    },
    "y": {
      "aggregate": "count",
      "type": "quantitative"
    },
    "color": {
      "field": "weather",
      "type": "nominal",
      "scale": {
        "domain": ["sun","fog","drizzle","rain","snow"],
        "range": ["#e7ba52","#c7c7c7","#aec7e8","#1f77b4","#9467bd"]
      },
      "legend": {"title": "Weather type"}
    }
  }
}