8:56 AM

Here is my final call for the storm as I see it based on observations of water vapor images, boundary layer observations, and radar presentation.  I think many of you are going to be pretty happy with what you’ll see!

SNOW MAP:

  Area One:  This area will be on the fringe of the precipitation shield with only light snow showers expected.  Accumulations of a dusting to 2 inches can be expected.

Area Two:  The latest water vapor images suggest the warm conveyor belt (supplier of moisture) is going to be rather strong, which means moisture will build back further west than earlier expected.  As such, I’ve increased snowfall totals here to 2 to 4 inches.  Some isolated locations may exceed 4 inches due to the up slope wind component enhance some of the precipitation.  

Area Three:  These locations will be just outside the best mid level dynamics, but will still get a period of moderate to heavy snow this evening.  Snowfall amounts of 3 to 6 inches can be expected in this area.

Area Four:  This is where we starting getting into some interesting mesoscale dynamics!  Based on the latest model guidance and the actual evolution of the boundary layer and coastal front structure this morning, this area has the potential to be impacted by the negative aspects of banding precipitation.  That is why I went with a range of 6 to 10 inches of snow with locally higher amounts.  The heaviest precipitation and strongest dynamics will still be east of Area Four, which means there is a potential for some localize breaks in the precipitation.  I still expect most locations to exceed 8 inches, however.

Area Five:  At least for this forecast area, this location is ground zero for a major snow storm!  I expect a general 10 to 14 inches to fall in this location with locally higher amounts.  There are several issues I want to touch upon here.  First, all of the best lifting at the upper levels, mid levels, and boundary levels are all present in this location.  There may be some initial precipitation concerns at the start of the heaviest precipitation as the 950 MB level to the surface will still be cooling to freezing at the start of the storm.  However, most precipitation type issues will be resolved by the time the heaviest precipitation will fall, between 1 AM and 10 AM Monday.  There may be some lingering precipitation issue on eastern Long Island as well due to the position of the 850 MB low as well, however the strong mesoscale lifting should counter act the warming of the 950 and 900 MB levels.    Convective snowfall will be a major determination on snowfall amounts.  There is a significant possibility that some locations will be impacted by snowfall amounts well above forecasted totals due to the intense banding that will be possible in this storm.  It is wise to keep this in mind, as the reduction in visibility will produce near blizzard conditions, which will cause significant issues for the commute on Monday morning.  If you can, stay home!