> So what's the lesson here? Check the WN site directly instead of depending on search sites.
Kayak and TripAdvisor will give you unpriced WN flights in their search results. You still have to check WN directly for prices, but it's useful for seeing what's available.
Being from Dallas (Southwest HQ) I know that Southwest doesn't allow other websites to use their booking and online flight pricing. Most airlines can be checked through Google Flights or Kayak but I know that I have to check with Southwest directly to compare their prices. BUMP: I guess I should have read the other comments as this has been said a dozen times.
Kayak and TripAdvisor will give you unpriced WN flights in their search results. You still have to check WN directly for prices, but it's useful for seeing what's available.