Technical Forecast

Synopsis:

 

Short-term, it looks like our second clipper system will make its' way through the Commonwealth for today, giving many areas a couple more inches of snow. That system should move out by tonight. Another low-pressure system moves to our north tomorrow, but will probably only give the north-central region a few flurries - everybody else should be dry. On Monday, high pressure in Ontario will give us partly to mostly cloudy skies and a temporary break from the snow. By Tuesday, however, another area of low pressure - this time coming up from the southern Great Plains - will move towards the Northeast, and this one looks like it could be pretty impressive. Once it moves offshore by Wednesday, areas of southeastern Pennsylvania could receive quite a lot of snow, which may mix with rain. Other parts of Pennsylvania will likely receive a good amount of snow from this area of low pressure as well, as it looks to be a pretty potent storm.

 

Short-term:

 

Today, the clipper is moving through Pennsylvania, which will give many areas of Pennsylvania a couple of inches of fresh snow for today. That system will move out by tonight, and another area of maximum vorticity will move through to the north of us for tomorrow, possibly producing a few snow flurries in north-central Pennsylvania. Tomorrow night into Monday, however, we will see an area of high pressure dry things out over the state. Winds will be from the north to northwest, since this high pressure will be up in Ontario. Thus, the temperatures will stay cold, and the 540 line will stay south of our area. However, this dry weather will not last long ...

 

Long-term:

 

An impressive area of low pressure looks to move up from the southwest, and it will be a potent one. The pressures don't look to be too low at this point (1004 mb. when it moves out over the Atlantic); however, it does have a lot of moisture drawn up with it. This will be due to the southerly influence of warm air from the Gulf of Mexico. Also, there is a huge area of high pressure that is set to move in over the northern Great Plains. One model has this high pressure getting as strong as 1050 mb! This is definitely an Arctic high that will be setting in, and the contrast between it and the warmer air down south will set up an impressive line of precipitation all the way from Texas through Pennsylvania. Once this low moves through, the Arctic high will be moving east, and giving us our turn of very cold temperatures (although it will not be as cold as in the Midwest). It is hard to say when the snow will begin, and also how exactly this low will track. The WRF has the low tracking a bit more to the north, which might mean a mix of snow, sleet, freezing rain, or rain for some parts of PA, but the GFS keeps the low a little bit more to the south. This seems more accurate, considering the general blocking pattern that has kept the eastern half of the country below average this winter, and the western half above average. All in all, a potentially very dicey situation this upcoming week!