Philly Weekend Weather Forecast

GFS model forecast for Saturday afternoon
GFS model forecast for Saturday afternoon

A deepening upper air trough will “pinch off” into a closed low to our west late Saturday.  Low pressure developing in the Appalachians wil bring rain to our area on Saturday.  On Saturday, rain starts as early as noon and definitely by 2-3 PM and becomes heavy by late afternoon and evening before tapering off Saturday night.  It will be humid with high temperatures around 77.

The closed off upper low will affect us on Sunday, which means a highly uncertain forecast. The GFS model has an area of rain staying out over the ocean, with our weather being dry but with a mix of low clouds and some sunny breaks possible during the afternoon.  Unfortunately, the models do poorly with the placement of precipitation around closed lows, so we could have partly sunny skies or even showers.  Will try to fine tune this later Saturday.  Depending on the amount of sun, it could be 72-77 as a high temperature.