Colder air has moved back into the region today riding in on strong NW winds and now our attention shifts to a couple different low pressure systems that will affect us tomorrow night and on Saturday. The first system will be a fast-moving (“clipper”) low pressure area dropping southeastward out of Canada towards the eastern Great Lakes on its way to southeastern Canada. This low will bring a cold front through our area tomorrow night and that is likely to cause snow shower activity between about 10PM and 4AM with light accumulations possible. While this system will not have a lot of moisture with it, whatever falls on Thursday night will likely be in the form of snow. The second event will feature a wave of low pressure that will come towards us from the Tennessee Valley early on Saturday. More moisture will be available with this low pressure area, but temperatures will be marginal as far as snow is concerned. It appears right now that “plowable” snow is likely from this early weekend system from around I-80 and points north and east (e.g. State College, PA to Lower Hudson Valley, NY to Boston, MA), but it appears as if we will enjoy a wintry mix here in the Philly metro region with snow, sleet, freezing rain and then ultimately “plain” rain. The precipitation should develop here probably around 4AM or so early on Saturday and then continue for a good part of the day. Some light accumulations are possible here in the Philly metro region before the changeover on Saturday, but the greatest likelihood for accumulations will likely be just to the north of here. Stay tuned.