A powerful Arctic cold front with a rapidly intensifying wave of low pressure will lift through the region on Saturday with a variety of impacts followed by a significant drop in temperatures into the single digits, 10s, and 20s.  The following details are what is expected for this evening on Saturday.

4 AM to 8 AM Saturday:

Scattered rain showers will develop throughout the as the cold front approaches from the west and the area of low pressure will approach from the southwest.  Temperatures in this time period will range from the mid-30s in the higher elevations and upper 40s in southern New Jersey.

8 AM to 12 PM Saturday:

As cold air is pulled east due to the intensifying low-pressure system, the rain will change over to heavy, wet snow in the Poconos and Catskills first and then gradually mix over to sleet and then snow southeastern Pennsylvania, northwestern New Jersey, and the central Hudson River Valley.  Rain continues for the Philadelphia metropolitan area, the rest of New Jersey, the lower Hudson River Valley, the New York City metropolitan area, Long Island, and Connecticut.  Winds will be increasing at 10 to 20 mph with gusts up to 30 mph as winds back from the southeast to the northwest.  Temperatures by the end of this period range from the mid-20s in the Poconos to the lower 40s along the immediate coast.

12 PM to 4 PM Saturday:

While the precipitation shield itself is moving east, all rain will change over to snow, even along the coast.  The snow will mix with sleet initially and then will remain wet along the coast.  Snow ratio will rise over the interior due to the colder air, supporting a drier snowfall in the Poconos and Catskills.  Winds will be from the northwest at 10 to 20 mph with gusts over 30 mph at times.  Temperatures will continue to fall throughout the entire region with temperatures by the end of the period ranging from the upper 10s in the Poconos to the lower 30s along the coast.

4 PM to 8 PM Saturday:

Snow rapidly ends from west to east in this time period while temperatures continue to fall and winds continue to hollow from the northwest at 10 to 20 mph with gusts over 30 mph.  Temperatures by 8 PM will range from the mid-10s in the Poconos and the upper 20s on the coast.

Due to the rate at which the cold air will be invading the region and the warm air in place ahead of this event, snow will accumulate faster on cold surfaces than the roadways, especially treated roadways, throughout the region.  This is a first call forecast and additional changes may be needed depending on data over the next 24 hours.