India, Sept. 3 -- 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.

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