A strong cold front will move through later Friday afternoon, between 5 and 7 PM.
As posted earlier, the very warm temperatures are NOT predicted to get into Philadelphia before the frontal passage.
Most of the lift dynamics will move to the far north of PHL and most of the instability will be found in southern Delaware, so any thunderstorms in the immediate Philadelphia area shouldn’t be very impressive.
In fact, the NAM has much of the heavy precipitation jumping past PHL and re-developing in southern areas. The GFS still has about 0.5 inches QPF for Philly, the NAM much less.
Update 4PM: The NAM appears to be correct. The precipitation seems to be dissipating as it reaches the PHL area.
High pressure builds in for both Saturday and Sunday. Fair skies and near seasonable temperatures. Highs on Saturday 62 and 67 on Sunday.
Low pressure departs by Saturday morning, however, an upper cyclonic flow on Saturday will cause windy conditions, cool temperatures with increasingly sunny skies.
Temperatures on Saturday will be around 52, but windy conditions with some gusts will make it feel colder.
On Sunday, a return flow aloft and upper level disturbance will cause some mid-level cloudiness around noon, but skies will again clear in the late afternoon. It will also be windy early on Sunday as this upper level disturbance moves through. High temperatures near 60.
