This exampe shows the temperature at 840 hPa and the geopotential height at 850 hPa from the GFS model (date 27/7/2016).
The idea is showing how to use the d3-marching-squares library as in the previous example, but adding isolines.
The colors represent the temperature and the lines the geopotential height. The example should have a scale, but the d3-legend library doesn’t seem to work with d3 v4. The isolines should be labaled too, and this is a quite difficult task.
The example is created with npm and browserify, so if you want to play a little with it:
Now you can see the changed page.
<!DOCTYPE html>
<meta charset="utf-8">
<body>
<div id="map"></div>
<script src="bundle.js"></script>