After tonight's frontal boundary and associated showers, more typical October weather will take over for the balance of the week. While temperatures won't be terribly cold, it will be nice and humidity will be tolerable. The pattern is setting itself up to trend a good bit cooler in the coming week as an upper trough establishes itself over the Great Lakes and Midwest.
While we won't be the coolest of cool nationally or coolest to normal compared to others, it will feel a bit November-like next week around these parts, especially early in the day. Some of the computer modeling out there for next week suggests lows below 40 in the western and northwestern burbs, with the potential for some frost in the normally colder climes across Eastern and Central Pennsylvania's rural areas. Colder temperatures lurk back across the Lakes and Upper Midwest but generally remain out there and won't push into our region.
Given this is a week away, it is possible modeling will modify the airmass some. I don't expect much chance between guidance now and a week out. It will trend cooler, as it should in late October, and I would not be surprised if a good chunk of Pennsylvania gets its first frost by this time next week.
There have been occasional "musings" about snow possibilities across Northern Pennsylvania and Upstate New York on the GFS but the model verbatim has shown nothing locally in the Delaware Valley regarding snow or snow chances on a modeled storm system that would impact us next week. Temperatures at the surface and in the lower atmosphere would simply be a bit too mild for snow around here IF that storm system were to materialize. Modeling is inconsistent within the GFS...and the Euro has not shown such a storm system in recent days. Anyways, colder air...although nothing historic in terms of cold...is on the way.