Today's gradual shift towards warmth ahead of a cold frontal passage tonight doesn't mean a ton of sunshine and warmth -- sun is at a premium, with perhaps only Southern Delaware and parts of South Jersey getting maybe a hint or two of sunshine through the course of the afternoon. It will be mild though later on today...with 60's eventually becoming the temperature that we're stuck with for a several hour window later this afternoon and this evening.
The cold front itself will be accompanied by a line of showers and perhaps some rumbles of thunder with it. Radar this morning had some thunderstorm activity back across West Virginia that was moving east and northeast -- this batch of thunder would be the activity that would work through parts of Pennsylvania later on today. There is a bit of separation in energy pockets with the front -- a northern batch of energy is shooting through the Great Lakes and up the St. Lawrence River through Southeast Canada with snow in Southern Canada and a mixed bag of wintry slop or rain for New England (the wintry slop mainly in the mountains). The second batch of energy in the Southern US will ride along the front but generally pass to our west and northwest later on today. It will also be weakening somewhat as the low responsible for the storm travels farther into Canada and separates itself from this energy wave along the front.
There will be at least some rain with the front and north and west of the city has a decent chance of getting steadier to heavier rains -- perhaps an inch of rain could fall in the Poconos and Central Pennsylvania later on as the remnant energy of the southern wave pushes up along the front this afternoon and evening. Locally, rainfall totals will be hard pressed to get much above a quarter inch in and around Philadelphia as the best energy with that southern wave goes west through northwest of the city later on. We'll get some rain later -- just not as much as the Poconos or Central PA potentially get.
Some thunder could accompany the front as it moves through tonight, with the front timed to cross the region between 8 PM west and 2 AM east. Winds could briefly gust with the frontal passage as well but it will mark the end of today's warmth and send us back to normalcy in temperatures for the balance of the week.