Weather Words: Super Fog

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If regular fog and dense fog weren’t dangerous enough - there’s another kind of fog that’s even more dangerous. It’s basically dense fog on steroids - and it’s called super fog.

Super fog forms when there is particulate matter in the atmosphere such as wildfire smoke present on top of dense fog.

Fog has been known to create pileups on the interstates, as cars go from an area with moderate visibility to an area with near zero visibility. Cars are unable to see the brakelights of the cars in front of them, causing the cars to rear end one another. In December of 2024 there was a 40-car pileup on the causeway over Lake Pontchartrain in Louisiana because of fog.

J​ennifer Gray is a weather and climate writer for weather.com. She has been covering some of the world's biggest weather and climate stories for the last two decades.