Here's the new Euro run, but I will have an update from the ensembles by 4 PM:

Don't take this run as the final solution, but it shows the general idea of a long-duration event. For Long Island, it's showing snow starting very early Monday morning and snowing all day, and then changing to sleet and rain for a period Monday night before changing back to snow for Tuesday afternoon and night.

This video goes from 7 AM Sunday to 7 AM next Thursday.