Why's temperatures important for cigars?

I know that temperatures have an affect on the humidity in the air (temps come down, RH goes up), but assuming that you can keep the humidity correct regardless of the temperature why is it important to keep the temperature correct to the ideal of 70 degrees?

What affects do temperatures have on cigars?

The main reason I ask is because I've thought about putting a humi in a room where the temps are only about 55 degres usually.

Thanks for any suggestions and explanations. Carl