You could check actual images from webcams, such as the ones from
WeatherBug; if you find enough with trees in view, they might give a useful indication of current conditions. Of course, by the time you see peak colours, it will be too late to plan a trip... unless you can leave a short notice.
I find this amusing, since our colours are now shades of brown... the bright
fall colours are long gone from around my house, and we're watching the sky for snow.