It may not be winter yet, but the National Weather Service in Upton has issued a*Winter Weather Advisory*, which is now in effect for Nassau county for this afternoon and evening.

More robust model runs coming in today have also prompted advisories to change to Winter Storm Warnings for areas north and west of NYC. In doing so, they are saying these that areas are going to receive 6 or more inches of snow. Certainly a big development, but is hard to argue given what I am looking at this afternoon.

The snow is just about on the doorstep for Long Island. It may struggle to reach the ground initially, but flakes are likely, especially across Nassau and western Suffolk. A mix with and eventual change to all rain is likely for all, especially in Suffolk where you guys may have to wait until the next storm to get a first taste of snow this season. That is, unless you believe the HRRR model. HRRR stands for High Resolution Rapid Refresh. This is one of the few models that actually runs every single hour, and it is certainly able to depict more localized precipitation types. The latest run shows some heavy wet snow all across Long Island (sans maybe just the twin fork) as late as 6pm. With the sun down and a frigid 36 hours leading up to the event, it may be enough for some accumulating snow, if the bursts are hard enough.

Now, even if you receive a few quick inches in your neighborhood, it will all get washed away tonight. It’s around freezing right now, but temperatures will rise overnight as a warm front lifts north of the area. Rain could be heavy at times overnight, which could lead to some localized street flooding. It will also turn quite breezy overnight with sustained east winds of 15-25 mph. Long Island could  see wind gusts over 40 mph! As if all of this wasn’t enough, the storm has also prompted some minor coastal flood alerts for the island heading into Friday morning (shown in the shades of green on the map at the top of the page).  The south shore back bays may see a 2 to 3 foot water rise above astronomical tides around the times of high tide.

Rain will taper off early tomorrow morning, with partial clearing likely by the late morning.  Friday afternoon will not be as harsh, with highs back up into the 40s. And that’s where they will stay, through the weekend and into next week. At least the weather will be dry during that stretch.

Prepare for a slow go this evening. Leaving early this afternoon would certainly be advantageous, if possible. Just allow plenty of extra time to get home and drive slowly and carefully.

Have a great rest of the day, and be safe!

Meteorologist Geoff Bansen