What Is Anvil Crawler?
Long, branching lightning that seems to crawl across the underside of a storm's anvil, sometimes for dozens of miles. In technical terms: Slow-propagating, highly branched intracloud or cloud-to-air discharges spreading horizontally through the stratiform or anvil region of a thunderstorm, often following positive cloud-to-ground strokes; visible from below as spider lightning.
Also called: Spider Lightning
Anvil Crawler In Plain English
Long, branching lightning that seems to crawl across the underside of a storm's anvil, sometimes for dozens of miles.
The Technical Definition
Slow-propagating, highly branched intracloud or cloud-to-air discharges spreading horizontally through the stratiform or anvil region of a thunderstorm, often following positive cloud-to-ground strokes; visible from below as spider lightning.
