Supposedly, a June 11th flash flood in Arkansas that caused waters to rise 24' in 3-hours, killing many campers at Albert Pike Park.
So, we have the symbol of Albert Pike, who was a famous 33rd degree Freemason who published a book called Morals and Dogma.
Then, we have the esoteric meaning behind June 11th, or 611, which is the SAM Code (Satan's Army of Masons) for identifying one as a mason.
Given that this flood was unprecedented, and came out of nowhere, I'm sure the conspiracy theorist will have a field day with it. If it was indeed manufactured, then this symbolism would have been intentional in order to send a message.