1:30 PM | **Snow to become more widespread and pick up in intensity later this afternoon...worst impact from nor'easter tonight into Tuesday **

[Latest satellite image of developing coastal storm]

Discussion

This two-part event is now about to enter its second phase in which the rapidly intensifying nor’easter off the Mid-Atlantic coastline will take control. The combination of the relatively warm western Atlantic Ocean waters, strong upper level energy, and an influx of brutally cold Arctic air from the northwest will cause this coastal low to explode off the coast from later today into Tuesday. In general, snow will gradually become more widespread and pick up in intensity later this afternoon; however, banding will also be a feature in which periodic brief heavier snow bursts will take place in scattered locations. The main effects from the nor’easter will be felt later tonight continuing into Tuesday when heavy snow will occur along with some blowing and drifting. In some parts of the Northeast US; especially, in the region between New York City and Boston, “thunder snow” may also take place with enhanced snowfall for a brief period of time. The snow will be of the dry, fluffy variety - not like the wet snow that fell last Friday night.

Snow accumulations are likely to range quite a bit across the Philly metro region with the greatest amounts to the north and east and the least amounts to the southwest. For example, the western part of Chester County could end up with 3-6 inches range by later tomorrow whereas Bucks County and interior South Jersey just to the east of Philly wind up with 6-12 inches, even more that that possible in coastal New Jersey. In the DC metro region, there will also be variable amounts of snowfall ranging from two to as many as 4 or 5 inches by early tomorrow. Meanwhile, in the region between New York City and Boston, this could turn into one of the all-time great nor’easters with 1-2+ feet of snow, 50 mph winds and some serious blowing and drifting. The storm winds down later tomorrow from southwest-to-northeast - early afternoon in DC, late afternoon in Philly, early tomorrow night in NYC. Next snow threat arrives by Thursday night...frigid cold next week.