The 50-year-old, writing in Doctor Who Magazine, dismissed the possibility of the show airing during the summer.
Moffat said: "Doctor Who in the summer? All that running down tunnels, with torches, and the sunlight streaming through your windows and bleaching out the screen? All those barbecues and children playing outside, while on the telly there are green monsters seething in their CGI-enhanced lairs? It's just not right is it? Be honest.
"For me, as a kid, when the afternoon got darker and there was a thrill of cold in the air, I knew that even though summer was over, the TARDIS was coming back! So yes, that's part of the plan, that's part of the reason for this little delay. But it's not the whole story."
Since its revival in 2005, each full Doctor Who series has premiered in the spring, with only the most recent run ending in the autumn.