Smart Driving : In a fog


When driving in fog, it’s best to run with your low beams on, whether day or night.

How you operate becomes more acute when the thick pea soup rolls in

For drivers it is one of nature’s worst nightmares. It can appear almost without warning. It can severely restrict your visibility and, in extreme cases, make driving nearly impossible. It can disappear in an instant or linger for days.

Fog, which occurs when warm, moist air mingles with cold air, creates havoc for truckers. For that reason, safely navigating a tractor-trailer in fog is an important maneuver taught in driver orientation classes at Freymiller Inc. “We have an area of our orientation we label ‘Driver’s Call,’ which refers to decisions made by our drivers out there that we’re not going to second guess,” says Harry Kimball, vice president of risk management at the Oklahoma City-based carrier, which received a 2009 safety award from the Truckload Carriers Association. “Any time visibility on the road is hampered, drivers are given specific instructions concerning company policy and common sense procedures.”

If the fog conditions are bad enough, shut it down, Kimball instructs drivers. “If my driver wakes up and he has visibility problems out the front of the truck, he’s going to have something worse in his rear view mirror,” he says. “My instructions are if you can’t see the nose of that Pete, and you can’t see behind you, go back to bed.”

Miguel Navarro, an owner-operator running under his own authority from Philadelphia, tries to avoid driving in fog whenever he can. “I try to divert myself from the route they give me,” he says. “Sometimes I pay a little more in fuel, but the most important thing is to get there in one piece.”

Roger Stout says to slow down gradually when you encounter fog.

Roger Stout, a Johnsrud Transport driver from Madera, Calif., is accustomed to fog from living in California’s San Joaquin Valley and tries to avoid it altogether if possible. “The best thing is not to go anywhere, but where I live it can stay that way all day,” he says.

David Frey, a Johnsrud driver from Star, Idaho, also tries to stay off the road in fog. If fog sets in after a rest break, he says, “If it’s too bad for me, I’ll find another place to stop. But the fog could be there all day till the next day.”

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Fog can hit anywhere, even on a clear day with blue skies. Kimball says locations such as the San Francisco Bay Area, Colorado’s mountains, Chattanooga, Tenn., and the Gulf Coast are prone to fog any time of year.

If you encounter a fog bank on a four-lane highway, Kimball tells his drivers, move to the left-hand lane. “Everybody’s afraid [in the fog], and they’re going to the right-hand lane,” he says.

When driving in fog, David Frey advises slowing down and not stopping on the road shoulder.

Navarro says he heads to the right-hand lane, because it’s safer than the left-hand lane, where some drivers continue to go the speed limit even in fog. Frey adds that driving in the right-hand lane allows you to keep an eye on the “fog line,” the painted line marking the right-hand edge of the roadway.

Stout says the rightmost lane can be dangerous real estate, too. “Guy in front of you can’t see any better than you,” he says. “You see all of these cowboy truck drivers driving 10 feet behind the dock bumper of the truck in front of them. That’s when I pull over and let them go.”

Following distance can be an issue. Frey says if he’s following a truck, he’ll attempt to keep the trailer lights in view unless the driver is going too fast for the conditions. “You have to adjust to the fog,” he says.

A universal no-no is stopping on the road shoulder. “Don’t enter the road shoulder, because you’re inviting a run under, and those are usually fatal,” Kimball says. “It happens all the time in the fog and the right-hand lane.” Navarro says stopping on the shoulder is never safe, even in clear weather.

Keep driving until you can exit to a rest stop, truckstop, parking lot or other secure area where you can wait out the fog. “Keep your speed moderate until you have clearance to get off at an exit,” Kimball says. “We’ll reschedule appointments if we have to or do what’s necessary to avoid injuries.”

Miguel Navarro will drive out of his way to avoid fog, even if he burns more fuel.

Drivers have different opinions on using emergency flashers. Navarro says his fog lights aren’t working, so he uses four-way flashers and slows down in the fog. Kimball advises drivers to use their emergency flashers, unless they have LED lighting, “which is prone to blind drivers behind you,” he says. “Click your LED flashers every 100 feet or so to let drivers know you’re there without blinding them.”

To Stout, four-ways are for emergencies only. “Some states require them if you’re climbing a hill,” he says. “If I see emergency flashers, I think someone is dead stopped.”

Driving in fog will take more time and wear you out faster. “If I’m tired, I’ll pull off, because driving in fog will drain you,” Stout says.

Tips for dealing with fog

• If possible, avoid driving in dense fog, or wait until visibility is at least a quarter mile.

• Slow down when you enter a patch of fog and increase following distance. If you can see the trailer in front of you in extremely dense fog, you’re driving too fast and too close.

• Drive with your low beams day or night. High beams reflect off the fog and create a white-wall effect.

• Turn on your fog lamps.

• Use your wipers and defroster to remove moisture from the windshield.

• Make sure you can stop within the distance that you can see.

• Roll down window and listen for vehicles suddenly braking.

• Use the “fog line” on the right edge of the road as a guide.

• Watch out for slow-moving and parked vehicles.

• Do not change lanes or pass other vehicles.

• Pulling off to the side of the road isn’t recommended.

Foggy place

Depending on who’s keeping track, the foggiest place in the world is either the Grand Banks off the island of Newfoundland, Canada, or Point Reyes, Calif.

Grand Banks is the point where the cold Labrador Current from the north and the much warmer Gulf Stream from the south come together, creating dense fog.

Among the foggiest land areas in the world are Point Reyes, Calif., and Argentia, Newfoundland, both with more than 200 foggy days a year, according to, the World Almanac and the Canadian Encyclopedia.

Point Reyes, 30 miles northwest of the Golden Gate Bridge, is considered the windiest place on the Pacific Coast and the second foggiest place on the North American continent, according to the National Park Service. The area is trapped in fog for weeks at a time, especially during the summer months.

Fog is essentially a cloud caught on the ground. It’s created when warm moist air mixes with cold air.

Deadly fog

Fog can be a deadly disaster for drivers. In 2002 on the Georgia-Tennessee border, fog caused a 125-car pileup that killed four people and injured 40 more.

In November 2002, fog triggered what may be the largest accident in California history. Close to 200 vehicles collided in that event, injuring 100 people. No one was killed.

Five years later, 108 cars and 18 tractor-trailers collided in the fog on U.S. 99 near Fresno, Calif. Eyewitnesses estimated visibility at two feet.

In 1990, a heavy fog led to a crash involving 99 vehicles along I-75 near Calhoun, Tenn., killing 12 and injuring 42. As a result, the National Transportation Safety Board prompted the state to install electronic speed limit signs equipped with fog sensors along this section of the interstate