Lightning sparks about 22,000 house fires each year in the United States, most often in June, July and August in the late afternoon and evening. Louisiana is fourth in the nation for lightning-related house fires.
Lightning starts in the storm cloud, where raindrops and ice particles collide, knocking off electrons and building negative charge toward the cloud bottom. Meanwhile, positive charge collects on the surface beneath the storm.
When the imbalance gets too strong, negative charge forks downward, drawing a stream of positive charge from below. When the two meet, positive charge surges upward, creating the brilliant flash.