 Like the remainder of the Southeastern United States , Florida has a winter maximum in dense fog conditions . Unlike the remainder of the region , the maximum in Florida contains roughly half of the annual occurrences per year , on average . Its summer minimum is less than the remainder of the Southeast . The annual number of heavy fog days ( with visibility of .25 miles ( 0 @.@ 40 km ) or less ) has ranged from 50 in Tallahassee , to 1 in Key West , the least foggy region in the state . The two types of fog that are most common in Florida are advection and radiational . Fog can be hazardous to early morning commuters . On January 9 , 2008 , when fog on Interstate 4 combined with smoke from a nearby fire , visibility was reduced to nearly zero . As a result , five individuals died in a 70 @-@ car pileup . 
