Thanksgiving weekend is the busiest time of the year for airlines. The worst days to fly are the Wednesday before Thanksgiving (this year, November 22) and the following Sunday (this year, November 26).  For the few days before the 23rd and the few days after the 25th, low-fare seats will be scarce. So, the further away from these days you can travel, the better. Low-fare seats are often more available on Thanksgiving Day and the next day, when everyone is relaxing after the Thursday meal…