The toll from the multi-car collision caused by "super fog" on Monday on Interstate 55 near New Orleans has increased to eight fatalities and 63 individuals injured, as reported by the Louisiana State Police.
Initially, the death count was at seven; however, one of the injured succumbed to their injuries in the hospital overnight, as per state police statements.
The accident, which involved a minimum of 168 vehicles, took place on Monday morning when heavy fog conditions significantly reduced visibility, according to Louisiana State Police. A substantial portion of Interstate 55, a 24-mile highway traversing Lake Pontchartrain near New Orleans, is anticipated to remain closed "for an indefinite period," as indicated by police.
Due to the collision, both Interstate 10 and Interstate 310 were also shut down, police disclosed. Louisiana Governor John Bel Edwards confirmed the incident in a statement issued on Monday.
Following the accident, emergency response teams labored for hours to clear wreckage from both the northbound and southbound lanes, as relayed by state police. Authorities reported that a section of the crash site on I-55 caught fire shortly after the initial occurrence. A comprehensive structural inspection is scheduled to occur once the bridge surface is fully cleared of debris, diesel, and other chemicals, police have indicated.
The "super fog" was a consequence of smoke originating from marsh fires in the vicinity, which combined with dense fog formation during the early hours of Monday morning, resulting in severely reduced visibility. In some areas, visibility was almost non-existent, creating perilous driving circumstances.
Super fogs usually develop when condensed water vapor mixes with smoke and moisture emitted from damp organic materials smoldering in nearby fires, such as vegetation, leaves, and trees, according to the National Weather Service. As a consequence, visibility can plummet to less than 10 feet, according to NWS data. This meteorological occurrence has been recurring in the area over the past several mornings, with the location of the densest fog and most hazardous conditions shifting from one day to the next, as indicated by forecasts.
Super fogs can be particularly hazardous when they manifest near or over highways. The localized nature of this weather phenomenon implies that visibility conditions can abruptly deteriorate over very short distances, creating a risky situation with abrupt reductions in visibility and vehicles traveling at high speeds on a highway. The severely limited visibility impairs a driver's capacity to respond to shifting conditions on the roadway.
The National Weather Service (NWS) released a dense fog advisory on Monday morning, covering a substantial portion of southeastern Louisiana, extending from Baton Rouge to New Orleans.
For several days, the NWS had been cautioning about the risk of dense morning fog in the region, which could be exacerbated in certain areas by nearby marsh fires. State police recommended that drivers activate their low-beam headlights if their visibility extended less than 500 feet ahead of them. The fog began to dissipate by mid-morning on Monday, and all fog advisories have been lifted.
While morning fog is typical during this season in the region, the state is currently grappling with extreme drought conditions across over 86% of its territory, elevating the risk of wildfires. This raises the likelihood of more episodes of "super fog" in the coming days and weeks, especially as cooler temperatures become prevalent.
Moreover, Louisiana continues to grapple with devastating drought and wildfire circumstances. Over 60% of the state is now classified under the most severe drought category, referred to as "exceptional drought," as indicated by the U.S. Drought Monitor. Only three months ago, none of the state's territory was categorized under "exceptional drought."