Translation:Tomorrow will be even better.
Based on other uses of 更 here, i don't think this is a comparison, but rather a quality statement that explicitly didn't compare. Think, "tomorrow will be quite nice". It doesn't compare to today, nor even leave you wondering, "Why are you saying tomorrow will be good? Wasn't today good?"
P.S. I asked a Chinese friend of mine, and he said that he would take this as an implied comparison with today.