The watch, which includes all of southern Connecticut, Westchester and Putnam counties in New York, New York City and Long Island, is in effect from 6 p.m. Thursday, Jan. 2, until 6 p.m. Friday, Jan. 3.
The hazards include 4 to 8 inches of snow, with strong winds of 20 to 30 mph and gusts of 40 mph, causing blowing snow.
Temperatures will be in the single digits and teens.
For drivers, visibility will be reduced to a quarter-mile or less. The snow and blowing snow will cause dangerous travel conditions.
The National Weather Service advises checking the forecast as the storm approaches the area.
For the rest of Tuesday, scattered snow showers are possible as revelers ring in the New Year. Overnight lows will be in the teens.
New Year's Day will be mostly cloudy, with a high near 30 with snow likely after 3 a.m. Light snow will begin Thursday, growing more widespread in the evening.
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