What is ‘super fog?’

ORLANDO, Fla. — Three people were killed in a several crashes along Interstate 95 early Thursday.

There was a lot of fog in the area at the time of the crashes.

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Over the past few days, there have been controlled and prescribed burns in Volusia and Brevard counties.

READ: At least 3 dead after several fiery crashes close 18-mile stretch of I-95 in Volusia County

A “super fog” event happens when condensed water vapor is combined with a mixture of smoke and moisture.

“It’s totally fine and then you run into a wall of that smog. You get an incredibly sharp drop in visibility,” meteorologist Brian Shields said.

READ: Orlando-based JetBlue pilot removed from cockpit ahead of takeoff for being drunk, officials say

The National Weather Service said visibility is lowered to less than 10 feet during the event.

“Super fog can be very dangerous when present over highways, and has been the cause of several large, multi vehicle pileups,” officials with NWS said.

Troopers said there was zero visibility in the area at the time of the crashes.

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