At around 5 p.m., firefighters responded to the fire at the large house, located in the 6700-block of Fieldstone Drive. Officials said the fire was isolated to the roof and spread quickly.
The roof was badly damaged. There is a gaping, charred hole over the garage of the home.
"Pretty much the whole second floor roof burned off," Tri-State Deputy Fire Chief Patrick Brenn said.
"Oh it was bad, it was bad. It started spreading really quickly," said Priya Patel, a neighbor.
The fire did not start intensely right way.
"There were just fumes coming out," Patel said.
Neighbors heard the fire start with a single bolt of lightning during a midsummer storm.
"That trick where you hear the thunder, and then the lightning. I heard it after half a second and was like, oh shoot, that's really close to me," said Nithin Reddy, a neighbor.
"We're pretty confident it was a lightning strike," Brenn said. "Neighbors recorded several lightning strikes in this area, to the point where it rattled the windows on their houses."
No one was inside the house at the time, officials said. No firefighters were injured while responding to the fire.
One family member returned to the home later Tuesday night to start retrieving clothing, a car, and anything that might be salvageable. The owner was away on a business trip at the time of the fire and is making his way back home.