In Fresno County, the California Highway Patrol says the foggy conditions led to a deadly crash near Selma.
The crash happened around 9:30 am at Parlier and McCall.
The California Highway Patrol say it appears the man in the pickup truck had pulled out from a stop sign on Parlier Avenue, ending up in front of a big rig that was driving on McCall.
"That big rig struck the front end of the pickup truck. The right front of the semi dragging that vehicle about 100 feet and through the intersection," said CHP Officer Mike Salas.
The pickup truck became engulfed in flames.
Investigators believe the morning's dense fog played a role in the crash.
"Even as I was rolling up, it was about 100 feet of visibility," said Salas.
The driver of the Chevy was ejected and pronounced dead at the scene.
The woman in his passenger seat was pulled out of the truck by a passerby and taken to the hospital with moderate injuries.
The driver of the semi was not hurt.
"We've had over a dozen of fog-related crashes not only on our local freeways, but our county roads and streets," Salas said.
One of those dozen crashes happened just down the road from the deadly accident.
The CHP says around 8:40 am, a tractor trailer was attempting a U-turn in the intersection of McCall and American when a van struck its left side.
"A second tractor trailer driving southbound on McCall impacted the other side of the tractor trailer that was across the lanes," CHP officer Ericka Islas explained.
The driver of the van suffered minor injuries.
Authorities say fog and speed were factors in the crash.
The California Highway Patrol is once again urging all drivers to be cautious in the dense fog.
"Reduce the speed, allow yourself some extra distance between the care in front of you and of all things, turn on those headlights. You want to make yourself visible," Salas stated.
"If you have to slow down, if you have to postpone your trip, do so. If you have to roll down your windows to listen for the approaching traffic, do so."
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