Philly Weekend Weather Outlook

Upper trough developing Sunday afternoon
Upper trough developing Sunday afternoon

An interesting pattern change starts setting up over the weekend, as an amplified jet stream trough begins to develop over the Great Lakes and weak disturbances begin to rotate through our area as a cold front slowly advances.  This amplified pattern is something we usually start seeing late August, not July, but it’s been a somewhat consistent feature of our cooler weather this entire year.

This amplified trough will eventually bring cooler temps and lower humidity to our area next week.

Saturday looks like the best day, although some clouds and showers may move in during the late afternoon. The approaching upper disturbances are more likely to bring showers and clouds Sunday. Details still uncertain.

Philly Forecast Change

The models have changed since yesterday and so has the forecast.

High pressure will block the advance of moisture from the south and  the  significant cloudiness previously expected will be less for later today, Saturday.

For Sunday, the expected easterly flow changes around to a southerly flow with less cloudiness. High pressure will nose down from the northeast, keeping us dry and reducing the cloudiness that had been expected.

Overall, a nicer weekend weather-wise is expected, specifically more sunshine on Sunday afternoon.

Weather… and Other Things 'Up in the Air'