Thunderstorms Approach As Heat Soars In Eastern PA: Latest Forecast

EASTERN PA — Thunderstorms with damaging wind gusts have a chance of impacting parts of eastern Pennsylvania this weekend, even as the heat continues to soar to near all-time historic high temperatures.

Friday will be the hottest day of the heatwave so far, the National Weather Service said, with a high near 95 and a heat index over 100 in parts of the region.

Scattered thunderstorms will likely not impact Philadelphia Friday, but could hit parts of the outlying suburbs between 3 p.m. and 9 p.m.

"Damaging winds could result in downed trees and wires," the National Weather Service added. "Heavy downpours could result in urban and poor drainage flooding."

Impacts will be focused along and north of the I-78 corridor.

A slight chance of rain and thunderstorms will continue from Saturday through Sunday, with thunderstorms becoming likely by Sunday night. But while the storms threaten, the heat will threaten the 100 degree mark, with a forecasted high of 98 on Saturday and 99 on Sunday.

That will come close to eclipsing the all time heat record for various parts of the region.

The heat index will be even higher.

The extended heat wave and potential continued lack of rain will also have impacts on air quality throughout the area. A code orange air quality alert is in place for the entire region Friday.

"Due to the persistent weather pattern this week, air quality is anticipated to deteriorate significantly, particularly along the Interstate 95 corridor from Washington, D.C., to Boston," AccuWeather meteorologist Renee Duff said. "The primary culprit behind this decline in air quality is likely to be ozone. It’s essential for residents in these regions to stay informed and take necessary precautions during this period."

Here's the full forecast:

Friday
Sunny, with a high near 95. Southwest wind 5 to 10 mph.

Friday night
Mostly clear, with a low around 75. Southwest wind 5 to 10 mph.

Saturday
A chance of showers and thunderstorms, mainly after 5 p.m. Mostly sunny and hot, with a high near 98. Heat index values as high as 103. Southwest wind 5 to 10 mph. Chance of precipitation is 30 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Saturday Night
A chance of showers and thunderstorms, mainly before 8 p.m. Partly cloudy, with a low around 79. South wind around 5 mph. Chance of precipitation is 30 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Sunday
A chance of showers and thunderstorms, mainly after 5pm. Mostly sunny and hot, with a high near 99. Southwest wind 10 to 15 mph. Chance of precipitation is 30 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Sunday Night
Showers and thunderstorms likely, mainly between 8pm and 2am. Patchy fog after 2am. Otherwise, mostly cloudy, with a low around 77. Chance of precipitation is 70 percent. New rainfall amounts of less than a tenth of an inch, except higher amounts possible in thunderstorms.

Monday
A chance of showers and thunderstorms. Patchy fog before 8am. Otherwise, partly sunny, with a high near 92. Chance of precipitation is 40 percent.

Monday Night
Mostly clear, with a low around 70.

Tuesday
Sunny, with a high near 91.

Tuesday Night
Mostly clear, with a low around 72.

Wednesday
Mostly sunny and hot, with a high near 97.

Wednesday Night
A chance of showers and thunderstorms. Mostly cloudy, with a low around 74. Chance of precipitation is 40 percent.

Thursday
A chance of showers and thunderstorms. Partly sunny, with a high near 87. Chance of precipitation is 30 percent.