Boom! A loud rumble barreled across the Philadelphia region this morning.
Tweets with the word "shook" skyrocketed moments after a loud thunder clap was heard about 10:20 a.m. Was it an earthquake? No, the loud boom heard was thunder.
NBC10 chief meteorologist Glenn "Hurricane" Schwartz says it was caused by lightning that amplified due to the cold air.
Rain moved into the area at the end of the morning commute. The thunderstorm is passing by the area and should be gone by 1 p.m. It made itself known knocking out power in parts of Delaware County and Roxborough.