Chilly Monday and Tuesday, then milder Wednesday, then light snow Thursday, then colder for a few days with light to moderate snows possible Sunday before a possible major storm the middle of following week

Plain-language summary:

It will finally turn cooler with more seasonable temperatures today, though it will still be mostly cloudy. A few breaks of sun with colder temperatures are expected for Monday before it turns milder for Tuesday and Wednesday and a light snow occurs on Thursday. It turns colder afterward, with a snowstorm possible in southern areas on Sunday. It stays cold through the following Tuesday, and then a major storm tracking farther north will likely affect the entire region the middle of the following week, but whether it warms up and rains or stays as snow is questionable.

Meteorological discussion:

 

Today will finally be cooler with more seasonable temperatures, but still mostly cloudy with lingering low-level moisture and a lack of a dry, arctic air mass to clear skies out. A weak, moisture-starved clipper moving southeastward through the Great Lakes will pass too far south to bring any snow to our region, just bringing some mid and/or high-level clouds instead. The clipper will bring somewhat colder and drier air with a bit of clearing for Monday and Tuesday as a weak surface high pressure from northern Ontario noses in, but the high pressure moves to the southeast by later Tuesday, causing a southwesterly wind and a warming trend for Wednesday.

 

Source: TropicalTidbits

 

 

By Wednesday, another weak, moisture-starved clipper approaches and could bring a little snow to areas north of the St. Lawrence River, before another weak, moisture-starved clipper approaches just behind it for Thursday. Unlike the previous clippers though, this clipper, associated with the polar jet, will be passing north of a subtropical jet fueled storm containing more moisture over the southern U.S. More likely, the systems to interact just a bit, perhaps enhancing the otherwise light snow in our region, but not really phasing completely and becoming a big storm until reaching Atlantic Canada. Most of the snow will occur over the Appalachians and just to the northwest, with the west to northwesterly flow leading to upslope enhancement there

 

A colder air mass follows briefly behind it with winds directly out of the north. Another moisture-starved clipper approaching will bring a reinforcing shot of cold air later Saturday. A subtropical jet fueled southern storm will approach our region next Sunday, with snow possible in southern areas depending on the exact track and intensity of the storm. In either case, surface high pressure to the north will maintain the cold air will remain behind the clipper.

Source: TropicalTidbits

 

After that, the PNA index turns slightly negative, which promotes cold air and upper-level troughs in western North America and warm air and upper-level ridges in eastern North America. It also promotes a storm ejecting from the Rockies and heading into the Great Lakes the middle of the following week. There has been a remarkably strong signal in all ensemble model guidance in this storm occurring, given how far out it is. However, the negative NAO and AO indices will counteract the northward motion of the storm caused by the -PNA and possibly prevent a true warm surge in our region, possibly forcing the low pressure system to remain to the south, and with antecedent cold air, substantial snow in our region, given all the Gulf of Mexico moisture such a storm would bring. For now, most model guidance suggests that the -PNA will win, and a storm passing to the north would bring warm air and rain instead of snow. The weather pattern favors storminess afterward as well. Although major snowstorms look unlikely for the foreseeable future, the snowfall deficit increase should at least slow if not stall with this somewhat more favorable pattern.

 

Source: Climate Prediction Center

 

Source: TropicalTidbits