https://www.vice.com/en_us/article/ne839d/imelda-blanketed-the-houston-area-in-almost-1-million-lightning-bolts

Tropical depression Imelda has caused nearly 1 million lightning bolts to form in and around the Houston area since Tuesday as the storm battered the region, causing heavy rainfall, over 20 mile-per-hour winds, and fatal flooding.

A known but understudied effect following bouts of extreme weather, this lightning cluster comes just weeks after parts of Oklahoma saw over a million lightning events in the span of 12 hours.