Reviewing the latest models for today, Sunday. Original forecast that much of the daytime will be dry still holds, but thunderstorms are expected to develop far northern Bucks and Berks counties by about 2 PM. Additional shower and thunderstorm development with a push southward towards Philadelphia should occur during the 4-8 PM time frame. Early evening hours may have severe thunderstorms with heavy rain.
With sunshine expected before then, there will be plenty of thermal energy for the development of moderate to severe thunderstorms. Check the NWS for severe storm warnings.
A moist southerly flow ahead a slowly advancing cold front will bring hazy skies and periods of cloudiness over this weekend. While previous model runs had suggested significant rain, especially for Sunday, the latest GFS model backs off from much of this precipitation and keeps most of Saturday and Sunday dry.
For Saturday, a weak warm front moves through Saturday morning with a slight chance of a shower. Some sun breaks out by afternoon. Very warm and humid. High 87
For Sunday, a repeat of Saturday with clouds and a chance of a shower in the morning. Some sun breaks out by afternoon , but increasingly cloudy late afternoon with showers and thunderstorms possible by evening into Monday.
So much of the precipitation is currently forecast to stay to our far north and west this weekend. Stay tuned.