First Widespread Snowfall Tuesday Evening Into Wednesday Morning

Before I get started talking about the clipper system impacting our region next week, we still have to get passed Sunday's rainstorm. It is still looking like a complete washout for our area...

Per the GFS, hefty rains will be setting shop over the Mid-State Sunday Morning into the Afternoon hours. The rain will begin to clear out after 10 PM Sunday Night.

Darker greens indicating the heavier rain in the above image. Now below is the total rainfall from this system. Still going with a general 1 to 2 inches of rain. Minor street flooding is likely. 

On the backside of this system, the winds will be blowing out of Canada delivering with it much colder air and even wrap around snowfall for the Northwest part of the state late Sunday Night into early Monday Morning. Snow amounts may reach up to 2 inches for those in the blue shading. The Lower Susquehanna Valley is not included in this, although back-end flurries are not out of the question. 

Over the last 24 hours, after reviewing guidance, I am becoming fairly confident that our first widespread snowfall of the year will be here Tuesday Evening into Wednesday Morning. Widespread does not automatically mean significant. This will be a clipper system that will dive down into the Great Lakes region, far south enough to deliver all of PA a period of light snowfall.

Picture below is valid Tuesday Night.

Now the question remains, will this just be your average clipper, or will it try to redevelop a low pressure system off the coast prolonging the snowfall? The GFS tries to do this. If it were to develop a little further south this run, it would of been a moderate snowfall for much of EPA/NJ. Still only light impacts for the Harrisburg area.

Picture below is valid early Wednesday Morning.

Notice the darker blues in Maryland and Southeast PA..that is the coastal trying to develop a prolonged period of snow. If these bands were to set up, perhaps a couple inches of snow may accumulate under whoever sees those bands of heavier snows. At the same time, notice the gaps to our west. This is a very quick hitter. We are looking at a 3-6 hour period of light snow. By the time most of us wake up Wednesday Morning it will be gone.

So how much snow will fall? I think many of us will fall under the coating to 1 inch category. Just enough to whiten up the ground for the first time this season. If you are reading this from Eastern PA and New Jersey, I would keep an eye out for an additional inch or two of snowfall. It depends how quickly the low pressure system redevelops off the coast.

-Chris