Philadelphia and the surrounding region woke up under a Heat Advisory on Thursday, with forecasters warning of a “bookend” day of storms sandwiching hours of dangerous, triple-digit heat index values, as the unsettled pattern that battered the region earlier in the week refuses to fully let go.
The US National Weather Service’s Heat Advisory took effect at 11 am and runs until 8 pm, covering Philadelphia and the surrounding parts of southeastern Pennsylvania. Highs are expected to reach around 90 to 92 degrees, with heat index values climbing as high as 100 to 102 degrees, marking the third consecutive day the region has recorded heat index readings above 100 degrees, according to Hoodline.
Weather Philadelphia: What’s Driving Today’s Storm Threat?
Meteorologists say Thursday is shaping up as a day of two distinct storm rounds. According to 6abc’s AccuWeather forecast, a warm front lifting through in the pre-dawn hours threatened to reignite storm activity that could linger into the morning commute, before hot and humid conditions took hold through the midday and afternoon.
A second round of storms is then expected late in the day, with forecasters warning that any stronger cells could bring damaging winds and an isolated tornado. Showers and thunderstorms are considered most likely from the afternoon into the evening, with roughly a 40% chance of rain, Hoodline reported.
Weather Philadelphia: How Does This Follow Wednesday’s Severe Weather?
Thursday’s heat and storm threat builds directly on the pattern tracked over the previous two days. On Wednesday, CBS News Philadelphia meteorologists Bill Kelly and Grant Gilmore placed the region under a NEXT Weather Alert, warning of a fresh round of strong storms overnight as a frontal boundary lingered across the area; the Storm Prediction Center had placed Philadelphia under a Level 2, or “slight”, risk for severe weather, with damaging winds and heavy rain identified as the main concerns.
Further west, the WGAL News 8 Storm Team had already issued an Alert Day for Wednesday and an Impact Day for Thursday across south-central Pennsylvania, with the Susquehanna Valley, including Harrisburg and Lancaster, likewise placed under a slight risk for severe storms and flash flooding. Thursday’s heat advisory and renewed storm threat effectively extend that multi-day alert into a third straight day of unsettled, hazardous conditions.
Weather Philadelphia: What Should Residents Do To Stay Safe?
With heat and storm risks overlapping, forecasters are urging residents to take precautions on both fronts. Recommended steps include drinking plenty of fluids, using air conditioning where possible, avoiding strenuous outdoor activity during the hottest part of the day, wearing lightweight clothing, taking shaded breaks, and checking on older neighbours or relatives who may be more vulnerable to the heat. Residents are also being advised to stay alert for sudden changes in the storm forecast given the potential for damaging winds and large hail during either round of storms.
Weather Philadelphia: What Does The Rest Of The Week Look Like?
Relief is expected to arrive by the weekend. A cold front will move through more slowly on Friday, keeping skies mostly cloudy and muggy with a chance of a few showers and a high near 87 degrees. Saturday is forecast to turn mostly sunny and noticeably less humid, with highs around 81 to 83 degrees, followed by a sunny Sunday near 77 to 79 degrees.
Labour Day itself is expected to be mostly sunny and seasonable, with highs around 80 to 81 degrees and lower humidity offering a clean break from the week’s heat and storms.
