What is Super Fog? The Mix of Smoke and Dense Fog Caused a Deadly Pileup in Louisiana

The National Weather Service called it ‘super fog’ — a combination of thick smoke from fires in marshy wetlands of south Louisiana and the fog that often hangs thick in the air on cool, windless mornings.

It was a deadly combination this week. Smoke spreading through the region from a marsh fire east of New Orleans combined with thick fog and reduced visibility on highways to near nothing. It caused a series of horrific crashes that turned a section of Interstate 55 near New Orleans into a virtual junkyard of mangled and charred vehicles.

Officials said 158 vehicles were involved. There were eight dead and 63 reported injuries as of Tuesday evening.

Super fog or smog?