...ni te cases ni te embarques.
In Spain today is the unlucky day and not a Friday of the same numerical persuasion. And, as the saying goes, you should neither get married nor start a trip. In order to follow that advice, it’s probably better that it is a Tuesday and not a Friday, since neither weddings nor trips are common on Tuesdays. Perhaps they were years ago.
I’ve searched online but can find no history of why it’s a Tuesday in Spain and a Friday in the States. Although I did find a few references (including Wikipedia) to it having been a Tuesday, the 13th when the whole mess at the Tower of Babel occurred… it would be fitting that in Spain the day were somehow tied to religion.