Philly Weekend Weather Forecast

A southerly flow around high pressure will maintain mostly sunny conditions for early Saturday with a high temperature near 70, However, some middle level clouds begin moving in during the afternoon as low pressure and a frontal system  approaches from the west.  It will be cloudy by late afternoon.

This system is expected to entrain some moisture from a tropical system in the Gulf resulting in heavy rain during the afternoon and evening on Sunday.  It will windy.  High temperature near 65 on Sunday.

GFS Sunday afternoon prediction

There are differences between the NAM and GFS models regarding the timing of the heavier rain, with the NAM having the heaviest rain in the evening

Clouds break around noon

The low level cloudiness breaks at noon, and temperatures still expected to soar to near or above 80 this afternoon.

A front moves through late Sunday night with some showers.  Much cooler weather for the beginning of the week.

Postmortem:  Low level clouds never broke for sunshine; this morning’s NAM (available about 10:30 AM) apparently showed this but not the GFS.  I posted before the NAM was released.   Either way, a poor model forecast. These sort of blown forecasts makes everyone skeptical about weather forecasting.

Sunday 4PM EDT Satellite