PHILADELPHIA (CBS) -- A very active weather pattern is setting up over the next week, with a parade of storms culminating in a strong coastal system next week that is looking likely to bring a chance of accumulating snow to the region. The first system, this weekend, won't do much beyond pumping warm moist air into the region and bringing some drizzle and fog.
On Sunday night, though, cold air will settle in behind a front and a fast-moving area of low pressure will zip by to the south. Originally the center of this low looked to stay pretty well south, but the latest runs of several of our models are bringing the precipitation farther north, leading to at least the chance of wet snow mixing with rain early Monday, mainly northwest of Philadelphia. Accumulation looks to be limited at best, owing to the rather mild weather coming off the weekend.
That changes with the next system, as cold air settles in over the region on Tuesday, with highs barely cracking the 40-degree mark. All of our major models have a strong coastal storm signal next Wednesday, as two pieces of energy phase along the coast. The uncertainty lies in the track and timing of the storm. The GFS model posits a faster and earlier storm, with the low moving through during the day Wednesday and heading pretty quickly out to sea -- cold enough for accumulating snow but keeping amounts more limited. The European and Canadian models have a slower solution, where most of the precipitation would fall Wednesday night into early Thursday, and also turn the storm up the coast, leading to the potential for heavier snow but also warmer air entering into the precip shield.
It's far too soon to pinpoint with any accuracy how much snow will fall or where an axis of accumulation might set up. There is always still the chance the storm tracks further north and becomes mainly rain, though the strength of the cold pool to the north should prevent the system from cutting too far inland. We also have to be mindful of when and where the two systems phase, as a later phase could lead to less precipitation overall.
The takeaway, five days out, keep a close eye on Wednesday of next week because it does appear likely that at least some parts of our area will see accumulating snow, and we will continue to monitor any changes in timing and track.
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