Why would you avoid DTW in NOV?? And even December for the most part. I can tell you that the worst of DTW winter is January and February and in most years early to Mid March however not this past year. November is for the most part quite dry and still in the 40's and 50's for the most part and December on average is just cold but very rare to get large snowfalls until after the new year. Also, DTW handles snow better than ATL handles summer thunderstorms in my opinion.