This Nicole Scherzinger photo contains
boater, leghorn, panama, panama hat, sailor, skimmer, straw hat, fedora, felt hat, homburg, stetson, trilby, and snap brim hat.
There might also be
dress hat, high hat, opera hat, silk hat, stovepipe, top hat, topper, beaver, street, city scene, urban setting, cavalier hat, and slouch hat.