CWS Forecast: Southeast Pennsylvania (Philadelphia)

Unseasonably warm temperatures are expected across the Commonwealth on Thursday, with highs reaching the upper 70’s to low 80’s along with a chance of showers and thunderstorms throughout the day. Friday will remain warm with partly cloudy skies before temperatures begin to cool heading into the weekend. Saturday looks favorable for daytime tailgating, with mostly cloudy skies and temperatures near 70. Rain and thunderstorms are expected to move into the area Sunday morning, with heavy rain possible as the system passes through. Temperatures will then fall into the 60s, with mostly cloudy skies and scattered showers continuing through Monday and Tuesday. Wednesday will bring more cloudy conditions, with temperatures near 60 and a continued chance of morning rain.

Day One: Thursday, September 17th, 2026

Mostly cloudy with a slight chance of showers in the evening and overnight.

High: 86°

Low: 71°

Day Two: Friday, September 18th, 2026

Sunny, becoming partly cloudy overnight.

High: 80°

Low: 64°

Day Three: Saturday, September 19th, 2026

Partly to mostly cloudy. Showers possible overnight, especially after midnight.

High: 80°

Low: 66°

Day Four: Sunday, September 20th, 2026

Overcast with a chance of rain all day, especially overnight.

High: 81°F 

Low: 66°F

Day Five: Monday, September 21st, 2026

Widespread rain especially in the morning. Mostly cloudy overnight.

High: 77°F

Low: 65°F

Last Updated on September 16, 2026 at 11:01 pm