Despite plenty of sunshine we only mustered a high of 36 at Philly International this afternoon; this was after a low of 23 AND a northwesterly wind between 10-15mph that made the wind chill in the middle 20s.
Overnight we'll have increasing clouds with lows in the middle 20s. Tuesday will feature an overcast sky with a short wave pushing through from the Great Lakes that will provide light rain along the coast, but a mixture of sleet and snow south of I-195 by the late afternoon. Highs will be in the upper 30s with little accumulation on the grass and colder surfaces.
It's not until after dark when we get some moisture from the low running up the eastern seaboard and with colder air filtering in we'll see a changeover to all snow with lows in the lower 30s. This wraps up by about lunchtime, but during the day thanks to a higher sun angle any snow that falls shouldn't stick much to roadways(so basically after the AM commute on Wednesday things shall be fine).
It shall be a heavier wet snow only amounting to a couple of inches south and east of the I-95 corridor EXCEPT west of Washington DC(with the short wave and colder air thanks to some elevation) and eastern Long Island where 2-4" may fall. The "jackpot" snowfall will occur as the coastal low "bombs out"(bombogenesis; the rapid intensification of a low that deepens 24 millibars or more within a 24-hour period) around the 40/70 Benchmark(40 N, -70W); this means the twin forks of Long Island out to Montauk and also Eastern CT heading northward into Southern New England can see 4"+ of snow(a half of a foot of snow isn't out of the question).
Behind the low we'll be in the middle 40s on Thursday, but then a surge of warm air works in for Friday with highs in the middle 60s!
So for now, think of warmer thoughts by the end of the week and you can always check out the 7-day forecast(any time) at www.scottderekwx.com/forecast.html .