What I saw looked quite a bit like a cold front; even if it was just a trough, that's still a characteristic of an extratropical system. The visible image you posted -- and a visible loop from earlier today -- clearly showed an exposed and elongated center to the south of the convective flare-up. It's one of those things where if it had done that a day earlier and wasn't in such a hostile environment, it coulda ended up like last year's unnamed subtropical system. But...I just didn't see in it what you did. Two qualified people can see different things, after all