SC, I forgot about Tessio's overcoat. It is an important inconsistency given the warmth of the day as is picking up a specialty cake (from Nazorine, no doubt) on a Sunday.
I wonder why FFC worked Pearl Harbor into the script anyway. Michael's enlistment could have been introduced through any number of scenarios.
I think the weather of that day is such a trivial thing that hardly anyone would know is really not worthy of discussion here. The only reason I know of it is that it figured big in my mother's recollection of that day (although one could look it up online on some internet site). As far as the cake goes, I suspect that Nazorine would have felt honored to show his respect for Vito on Vito's 50th birthday by baking a special goodie.
FFC may have used the Pearl Harbor story as the catalyst for Mike to enlist to further his showing that Mike was more "American" (i.e. more "modern") than the rest of the family. That obviously changed after Vito was almost killed by the shooting outside his office.
