Thanks for the response Dana, and for that comment that the WIC may
  be off a day.  
 
I MAY have found another instance of the WIC record being plotted
  being off a day, but I'm not sure.  I was investigating the record
  MaxT (80) for Dec 25 at DFW.  In trying to view the various forecasts
  and d/(prog)/dt info, along with the WIC, I first set the time to be a
  period ending 06Z on Dec 26, as can be seen in the graphic below.  In
  doing so, I think it may be keying in on the record for Dec 26 (83),
  and not the 25th.  Though I may have loaded improperly.
Both records are likely to be matched or beaten, BTW.