The coldest air of the season is about to arrive into our area. Temperatures will manage the low 40s for New Year's Eve and New Year's Day, but beyond that we'll be struggling to get much above the freezing mark.
We'll be under weak high pressure to start Monday, but it will be quick to move out to sea. Consequently, we'll start with sun but finish the day with clouds. On the plus side, it won't be nearly as windy today as it was on Sunday, although there will still be a bit of a breeze out there.
A weak disturbance in the upper atmosphere could bring us a brief snow shower overnight tonight, but most likely not until after midnight, so New Year's Eve plans should be fine. If you'll be outside tonight, you will definitely want to bundle up as temperatures will be in the 30s with wind chills in the 20s.
This disturbance will be slow to exit, so there will be plenty of clouds around for New Year's Day with some flurries possible. If you're heading to the Mummer's Parade, again you will want to dress warmly, as temperatures Tuesday morning will be slowly rising through the 30s with wind chills in the upper 20s to near 30.
A high pressure system coming down from Canada will arrive by Wednesday. This Canadian high will drop our temperatures to the coldest levels we've seen all season. It will stick around for the rest of the work week, holding our daytime highs between 30 and 35 and our overnight lows between 20 and 25. Since high pressure means "happy" weather, we won't have to deal with any rain or snow for the rest of the week.
A separate area of high pressure will begin to approach us from the south by the weekend. It should get here by Sunday or Monday. Temperatures will still be chilly on Sunday, but not quite as cold as they will be for the second half of this week.
If you like the cold, enjoy it this week. Don't forget to look for updated forecasts throughout the week on Phillyweather.net. Have a happy new year!