Thank you. Yeah i used to just use all shades of blue but it got very hard to see the towns when the colors got really dark. I figured i would parallel the colors that the NWS uses, more or less. Its easier on the eyes and makes more sense.
The color gradient is generally (example): 0 white, T-2 light blue (sub advisory lvl), 2-4 blue (advisory), 4-8 yellow (low end warning) 8-12 orange (warning), 12-18 redish pink (amounts 10+, major), 18-24 purple (amounts over 15 historic/major), green 24-40+ (extreme, rare)
This is Mar 2018, an example of why i changed the colors after the blue shade...