Philadelphia, Pennsylvania – Expect summer heat and rising humidity to take center stage Monday, July 21st, as Philadelphia kicks off the week with sunshine and temperatures climbing into the upper 80s. Outdoor workers and commuters along I-76 and Broad Street should brace for a midday heat index near 101°F.
According to the National Weather Service, Monday will bring mostly sunny skies and a high near 85°F in the city. Calm morning winds will shift from the north around 5 mph. While dry conditions dominate early week, a return of thunderstorm chances is expected Tuesday night into early Wednesday — especially north and west of the metro area.
Tuesday stays sunny and warm with a high of 83°F. But by Tuesday night, skies will turn partly cloudy with lows dipping to 64°F before moisture builds midweek. Wednesday features a high near 86°F, with possible evening storms, followed by a steamy Thursday peaking near 90°F.
The extended outlook suggests increasing instability by late Friday into Saturday, with scattered showers and storm chances returning just in time for weekend plans. Friday’s high will top out near 85°F before humidity and unsettled skies linger into Saturday.
Safety Tip: Limit strenuous outdoor activity between 1–4 p.m. Monday. Hydrate frequently and never leave pets or children in parked cars.
Five-Day Forecast:
- Monday, July 21: Sunny, high 85°F, north wind around 5 mph
- Tuesday: Sunny, high 83°F; partly cloudy overnight, low 64°F
- Wednesday: Mostly sunny, high 86°F; slight storm risk at night
- Thursday: Sunny and hot, high near 90°F
- Friday: Partly cloudy, high 85°F; 30% chance of evening storms
- Saturday: Mostly sunny, high near 94°F with continued summer heat
