Thanks for the quick response.We have visited in January three times.
In our experiences, the pros have been that the crowds are manageable (despite the high volume of guests due to the marathon and MLK day), some nice weather days in the 60s and 70s, I don't think it rained once from what I can remember, and we got good deals on the resort which helped us stay at the Poly twice and we fell in love with it.
In our experiences, the cons have been that the temperature can fluctuate and be unpredictable with some super cold days specifically in 2010 where we needed hats and gloves and a coat and some rides including our beloved Splash Mountain are down for regular rehabs. I cannot speak to the groups and tours as I simply don't remember.
Overall I think it's a nice time to go. The only reason why we don't is that we are from the Northeast and prefer to go during warmer months when snow won't be a factor at all in travel. In fact we may go back to the January routine for a few years while I am (hopefully!) in grad school.
Happy planning!
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