I don't think there will be a new episode airing May 19. I just checked the schedule on nick.com and it just says nicktoons tv as opposed to a new spongebob episode. 

I KNOW HOW YOU FEEL. I KNOW THAT THEY HAD LAST SATURDAY MORNING FOR A NEW EPISODE AS SCEDULED BUT I HAD TO GO TO TAMPA FOR ORIENTATION FOR BLOCKBUSTER BECAUSE I STARTED MY JOB AND I STILL DONT KNOW IF THEY DID OR NOT. AND I HAD MISSED THIS MORNINGS EPISODE SO I REALLY DONT KNOW WHAT NICK IS DOING MAYBE THEY SHOWED THE LAST FEW NEW EPISODES WITHOUT US KNOWING AHEAD OF TIME BUT I WOULD LIKE TO SEE THE REST OF THE NEW ONES. NICK.COM  NEEDS TO CORRECT THAT AND AS FOR YESTERDAY THEY HAD ON THERE KARATE ISLAND AND THE NEW LEAF WHEN IT WAS WHALE OF A BIRTHDAY AND KARATE ISLAND. THAT MAKES ME WONDER. DID THEY SHOW THOSE NEW EPPYS PLEASE LET ME KNOW I NEED TO KNOW. I WANTED TO RECORD THEM AND WHEN  I CHECKED FROM MY DIRECTTV SYSTEM THEY HAD OLDER EPISODES.