Out of where? Most, if not all, of th the Island will more than likely be rain at that point, but it will be breezy and could be raining heavily. I’m no good at guessing what the airlines do though, so I’m not much help in that department lol
With regards to this storm how much snow and how quickly it turns to rain will be very tenuous and will be based largely on surface wind directions. The more northerly the component, the more/longer its snow and sleet. If it turns east right off the bat, however, it’s probably just a bit of snow/sleet than rain.
If I had to guess at this point, I’d say a slushy coating to 1/2”, maybe 1” on like Janes hill or something in NW Suffolk on grass, car tops, etc. for western LI away from the shore then rain. The one caveat is that Cold Air Damming tends to be underdone on the models. Should that happen and it stays colder longer we could be dealing with wintry precipitation. That’s my one concern with this storm. If that happens, it turns into a snow to prolonged sleet to rain, which is no fun