I suppose that works, though in July the "Cool category" (if we follow the terminology in your prior post) tends to stick quite closely to the coast.
Here are the sample maps that include the new category, following your suggested colour scheme:
Jan:
JanTemp x11.png
Jul:
JulTemp x11.png
Tbh I haven't thought too much about the placement instructions yet. Though personally I plan to use an alternative method to create the temperature maps anyway. I made a little test continent and created a basic greyscale height map for it:
HMap Test.png
The scale used is the following:
RGB Elevation 0 -150 m 1 -125 m 2 -100 m 6 0 m 255 6225 m
And converted into the standard elevation map:
HMap Coloured.png
Then as a test I've created a map of surface-level temperatures in July. Again, in greyscale, ranging from -50 to 50 °C (200 to 0 RGB, darker=warmer). Here are the different temperature bands with the continent shown on top, gradient mapped at 10 °C intervals:
JulTemp Test.png
Colour Temp (°C) Red 30+ Orange 20 to 30 Yellow 10 to 20 Green 0 to 10 Light Blue -10 to 0 Blue -20 to -10
Then I've blurred the temperature bands, creating a gradual transition. The elevation map can be directly translated into an "elevation adjustment layer" if the temperature is assumed to drop in a linear fashion with incresed elevation, and then applied as an overlay over the surface-level temp map. The final map (btw, the blurring is not shown here in the background layer, those are the original temp bands):
JulTempFinal Test.png
If you use this method you can easily include as many temperature layers as you like, since the elevation part is essentially automated, though it's a bit more work to create the gradual map of sfc-level temperatures. And of course you need a fairly detailed height map in greyscale for this method to work.