Please allow the user to select linear and log scales for the color of map data. I noticed, particularly with snowfall rates, the log scale makes it difficult to interpolate. The scale in inches/hour is:
0 0.07 0.24 0.7 2.0
Something like:
0 0.25 0.75 1.0 1.25
would be easier use. In addition to or instead of, show tick marks to help with interpolation.
This might not be as useful as you may imagine since it would result in the scale colormap will be stretched so you see lots of purple and blue, and very little green and red. This will make the data on the map harder to interpret.