Sneaky snow event suggests slippery commute this evening

John Cifelli, Meteorologist | December 15, 2017 | Weather
  • Developing low deepens earlier and further west than expected

  • Snow begins early this afternoon south and west, then spreads north

  • Accumulations likely statewide, highest totals east/central

We have a surprise snow on our hands this afternoon, as a coastal low will develop along a coastal frontal boundary and slide by to our south and east. All week, it appeared that the low would develop and deepen too far east for much of any accumulating snow to fall. Instead, upper level energy embedded separately within the Arctic and Subtropical jet streams are arriving across the mid-Atlantic in slightly better sync. This allows for this energy to phase a bit earlier, and the surface low to develop further west. As a result, what looked to be an accumulating snowfall for the fish swimming in the Gulf Stream instead will fall on New Jersey roadways this afternoon.

Expect snow to begin between noon and 2 p.m. in the southwestern New Jersey and the Philadelphia metro area. It will spread east, and gradually to the north as well by the evening commute. Snow will fall steady or even heavy for a brief period along and south of I-195 as the late afternoon progresses. Further north snow will be lighter. The ability to accumulate on roadways will depend on whether or not transportation departments are getting the brine and salt vehicles out quickly enough.

If you can avoid the roads this afternoon, it is recommended. Very cold surfaces, good snow growth ratios, and the surprise nature of this quick snowfall means that things could deteriorate quickly, particularly along the southern half of the Parkway and Turnpike. It’s a quick mover, as all snow will end by 7pm. But by then the damage is done, because the heaviest snows coincide with the Friday afternoon and evening commute.

Expect a general 1-3″ across the state, with less in the Skylands region and far northern New Jersey. As much as 3-4″ could fall along the Parkway corridor south of Monmouth County and north of Cape May. Again, it’s a brief period of steady snow, so the weekend looks clear but cold.