The latest composite radar, satellite and surface pressure analysis is shown above. I've noted the center of the rapidly deepening area of low pressure located to the East of Virginia Beach.
As you can see, precipitation is increasing rapidly to the North of the center, with moderate to at times heavy snow falling from near New York City on to the East/Northeast...
Precipitation has been cycling between snow and a rain/snow mix across especially Southern portions of NYC for the last couple of hours, but we should see a transition to mostly snow as the afternoon progresses.
Snowfall rates will intensify across the region during the afternoon and evening, reaching 1-2 inches per hour with localized snowfall rates near 3 inches per hour, especially in thunderstorms that are likely to form at times.
Snow has just recently begun to fall in the Boston area, and will increase as the afternoon progresses.
The Governor of Massachusetts just announced that he's signed an Executive Order banning vehicles from the roadways effective 4pm EST. That will effectively "close down" the state at that time.
The wind is really starting to kick-up just offshore. The chart below shows the wind and pressure trends at a data buoy off the coast of Long Island. As you can see, the barometric pressure (green) is dropping rapidly, and the winds (blue and red) are increasing accordingly:
This trend will escalate and spread inland throughout the afternoon and evening, with all out blizzard conditions developing over time. Gusts are likely to exceed 50 mph at times late this afternoon through tonight in the Blizzard Warning area shown in orange on the image below:
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