*Snowstorm update and new Euro run*
The National Weather Service came out with an aggressive opening bid snow map (1st image) with 12 to 14 inches for Long Island, with the exception of eastern Suffolk. I would feel more confident forecasting 8 to 12 inches with 5 to 8 inches for southeastern Suffolk.
The new 18Z Euro run (2nd image) just came out and it holds the line with the snow for Long Island but it lowers the northern fringe in New England as the high snowfall totals narrow as you head ENE from PA towards Long Island and southern New England.
I'm very curious to see the HRRR model when we get within range. While the HRRR runs every hour and goes out 18 hours, 4 times a day it extends to 48 hours, so we're almost within range.
The start time for Long Island is generally 3 PM to 5 PM on Wednesday from west to east with near-blizzard conditions from 11 PM to 5 AM with wind gusts of 40 mph to almost 50 mph (max gusts are shown in the 3rd image). There should be a period of sleet/rain for southeastern Suffolk, which will hold snowfall totals down there.
The snow will only slowly melt until we get to next week, as you can see the cold temperatures for Long Island in the 4th image, especially morning lows, and we also have a very low sun angle and short days.