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1.
A study tool most frequently used by college students which consists of an Adderall and a 5 hour energy. There are two methods of consuming a Philly Thunder. Either chase the Adderall with a 5 Hour Energy or take the adderall and consume the 5 hour energy a few hours later. It can keep a person highly alert and attentive for 12 hours straight. It must be done with a 5 hour energy or else it is simply just called an energy drink with adderall. All other Philly Thunders are imitations. The Philly Thunder originated in Philadelphia, Pennsylvania
Conversation at 10 AM before an exam

Drew:"Yo dog, this Philly Thunder is crazy. Its been 10 hours and Im still going strong"

Jamal:"I know man I did one a few hours ago and Im feelin thunderous"
by Blue Bitch December 21, 2008
 
2.
This popular studying aid originated in Philadelphia and consists of taking an adderall and consuming an energy drink simultaneously to pull an all nighter studying for an exam. You can also take the adderall and consume the energy drink a few hours later for the same effective boost. It is most commonly practiced during finals week at universities across America.
Overheard at a college library:
"Yo man, I did a Philly Thunder last night and aced the exam. That shit was wild"

"Yea that Philly Thunder will keep you buzzin for hours"
by Petey Mooms December 17, 2008