Lightning Damage at GSP Airport
on 28 July 2000
Bryan P. McAvoy
NOAA/National Weather Service
Author's Note: The following report has not been subjected to the scientific peer review process.
On Friday evening, July 28th, a fierce thunderstorm affected central
Greenville and Spartanburg counties. The storm was unusual in that it
drifted slowly west, dropping torrential rain (2.97 inches at our office).
Hail fell for nearly 30 minutes at the airport, reaching the size of dimes
on two occasions. The storm also had nearly continuous cloud-to-ground
lightning. In addition to the several trees which were struck at the
GSP airport, the main runway was also hit. Lightning blasted an 18 inch
diameter hole in the runway, temporarily closing the airport.
Figure 1. A series of four images showing lightning damage to trees at
the Greenville - Spartanburg International Airport, caused by a severe
thunderstorm on 28 July 2000. From left to right, a tree in the long-term
parking lot, along with a close-up of the same tree. Looking up the trunk,
the scar caused by the path taken by the lightning along the bark of the
tree. Another tree damaged by lightning was just a few feet away.
A few pictures of the trees hit by lightning are provided above. Click
on the image to see a larger picture. The first three pictures are of
the same tree. This is a wonderful illustration of how lightning works.
The lightning strike followed the conductive, living outer layer of the
tree. While bark was knocked off in a 4 or 5 inch width along the path,
a much smaller channel was cut in the wood of the tree. The width of an
average lightning channel is somewhere between that of a pencil and a
human finger. Thus, the deeper gouge in the tree was that of the lightning