I've been having the same problem since the wunderground web site update. I get no response sending them emails so who knows when this might get fixed. Please post if you know a resolution to this issue.
For future wunderground upgrades, "If it ain't broke don't fix it!" The new platform will not upload my webcam and causes my Firefox 48.0.2 to crash. Also takes forever to load on a current browser and operating system.