The Catatumbo Lightning (Spanish Relámpago del Catatumbo) is an atmospheric phenomenon in Venezuela. It occurs strictly in an area located over the mouth of the Catatumbo River where it empties into Lake Maracaibo.
The frequent, powerful flashes of lightning over this relatively small area are considered to be the world's largest single generator of tropospheric ozone, that is, ozone that does not replenish the stratospheric ozone layer.
It originates from a mass of storm clouds that create a voltaic arc at more than 5 km of height, during 140 to 160 nights a year, 10 hours per day and up to 280 times per hour. It occurs over and around Lake Maracaibo, typically over the bog area formed where the Catatumbo River flows into the lake.