Pennsylvania and New Jersey Record Warmest September in a Decade With Widespread Heat and Dry Conditions
PHILADELPHIA, Pennsylvania — September 2025 closed out as the warmest September in a decade for inland areas of Pennsylvania and New Jersey, with temperatures running several degrees above normal and rainfall totals lagging far behind averages, according to the National Weather Service in Mount Holly.
Philadelphia and Other Cities Swelter
Philadelphia recorded an average September temperature of 73.0°F, which was 3.1°F above normal, marking its warmest September in roughly 10 years. Other inland cities, including Reading and Allentown, also logged significantly above-average heat.
Rainfall Deficits Across the Region
Rainfall was sharply lower than normal across much of the region:
- Mount Pocono: 1.23 inches (7th driest September since 1901, more than 4 inches below normal)
- Allentown: 2.66 inches (2.18 inches below average)
- Philadelphia: 1.79 inches (2.61 inches below average)
By contrast, coastal areas saw more typical totals, thanks to onshore winds. Atlantic City International Airport reported 4.36 inches of rain, slightly above normal.
A Better Picture Than Last Year
Despite the widespread heat and dryness, forecasters noted the region is in better shape than September 2024, when a developing drought began to grip Pennsylvania and New Jersey. Still, the sharp deficits this year are raising concerns for fall water levels and agriculture.
The September 2025 weather pattern underscores how climate extremes continue to impact the Northeast, with record warmth and patchy rainfall reshaping seasonal expectations. For more weather updates and regional forecasts, follow ChicagoMusicGuide.com.