So thanks to Kenny now we all know the location of Wellington.
I made a little map here to give you an idea of how long Clementine, Omid and Christa walked to get to where they are right now.
Now I looked at the biggest cities in Michigan and the only one big enough to match episode 5's slide is Detroit, so Wellington must be somewhere outside Detroit.
How long do you think it'll take them to get there once they deal with Carver? Christa said it'll be months.
It's already December in episode 2 so we can assume we'll get another time skip and get there in 2 or 3 months for it to be still snowing like in the episode's slide.