The folks in the video above aren't watching a fireworks show but rather the near-constant lightning strikes that occur over Vaenezuela's Catatumbo River almost half of the year. Apparently, sailors have dubbed the lightning "Maracaibo Beacon" because it can be used as a navigational aid. According to the excellent Atlas Obscura, there might be as many as 280 strikes per hour during 10 hour stretches. From Atlas Obscura (photo below from Wikipedia):
(The phenomenon) was first written about in the 1597 poem "The Dragontea" by Lope de Vega. De Vega tells of Sir Francis Drake's 1595 attempt to take the city of Maracaibo by night, only to have his plans foiled when the lightning storm's flashes gave away his position to the city's defenders.Relampago del Catatumbo
It's still unknown exactly why this area--and this area alone--should produce such regular lighting. One theory holds that ionized methane gas rising from the Catatumbo bogs is meeting with storm clouds coming down from the Andes, helping to create the perfect conditions for a lighting storm.