Creating a set of rules, for IF AND statements

[GreenhouseNS]

Hello,

I am hoping to create a spreadsheet with an existing set of rules, that I can then copy and paste my temperature and humidity readings into to generate a column of values (column C). Ideally I would be able to get the values that are posted in the chart below, but would settle for simply assigning red, green or yellow colouration to column C. 

Any suggestions? It seems there is a limit to the number of IF AND statements you can make...

Thanks in advance!

[#2]

@GreenhouseNS 

Do you want to create conditional formatting rules? If so, you could create a simple set of 4 rules of type "Format only cells that contain", but please provide more details.