Our flight home via Southwest on May 15th is currently priced at $243. To my recollection I have never seen a flight this expensive more than 30 days in advance.
To put this in context: Of the 19 flights home that day, the next most expensive is $157, although the flight after ours now shows Sold Out. There are still many flights listed at $92, and these will probably go down in price next Tuesday.
BTW: We are booked at $56, and I was hoping the price might even go down. lol