After saw the set pict, I have some pergunta and this are some theories to answered that question, I hope you enjoy read it

1. Why emma the one who meet him in NY? Nael got the postcard, I honestly though after he receive that postcard, he immediately fly to storybrooke and procurar for emma

Theory 1
nael decide to mover on. He doesn't know about henry and decided that emma is his past and need to stay as his past.

Theory 2
he feel guilty and can't face emma yet

2. Why emma in NY? why she willingly leave her family and storybrooke to meet someone who broke her heart?

Theory 1
He called and ask her to meet him. I don't think emma want nael and henry to meet, emma probably still hate nael, but if nael (or august! God please) explain to emma what happen, she probably want to give him a change, but still she didn't want a chance henry meet nael, so she decided to meet him in his city

Theory 2
bael, yup rumple decide to ask emma a "favor". He want emma to find bael and turns out nael is bael so she doesn't have a choice. She have to leave and meet him

Do you have other pergunta or theory after saw that picture?

And if you haven't see it yet, you can see it in here:
www.fanpop.com/clubs/once-upon-a-time/images/33032812/title/set-picture-12-12-12-neal-emma-reunion-photo