Thick fog is a driving hazard in many locations of the west U.S. In the Pacific Northwest, it comes up largely in winter. In California’s main Valley — wherein some roads have actually been called amongst the most dangerous in the world because of fog — the fog season starts v the very first heavy rain in fall and also goes till March.

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How to journey in Fog

Just favor there room different varieties of snow, there are many species of fog. Oregon has actually freezing fog that have the right to coat the road prefer black ice. California’s “tule fog” usually develops in low-lying areas that commonly have bulrushes (tule, express “too-lee”) cultivation in them. Tule fog can reduce visibility top top a stretch that highway to just a few feet, while other locations are practically clear.

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This is true that fog anywhere: You have the right to be driving in addition to enough visibility and then unexpectedly go with a patch wherein you have the right to barely view the road.

When fog’s an issue, here are advice to save you safer on your drive.

slow down and turn off her cruise control. Most crashes happen because the driver’s walking too quick for weather conditions. Drive with enough stopping an are so you deserve to stop in the street you deserve to see. Don’t use high-beam headlights. Castle won"t shine with the fog however just reflect the light ago in your eyes, making that worse because that you and other drivers. Usage low-beams. In really thick fog, use front fog lights in addition to her low-beams if you have actually them. Never drive using only your parking or fog lights. It’s illegal and also unsafe. Usage rear fog lights if you have actually them as soon as visibility is much less than approximately 300 feet. Fog lights have to be rotate off as soon as visibility is normal. They have the right to be distracting because that oncoming drivers. Oregon legislation says fog lights have to be rotate off once within 500 feet of one oncoming vehicle and also within 350 feet once following another vehicle. Minimization distractions. Revolve off music and also don’t talk on her cellphone, therefore you deserve to listen for traffic you might not be able to see.


save your headlights clean. Gain in the habit of clean everything them turn off whenever friend fill her gas tank. Save the windshield clear and use the defroster to avoid fogged windows. Keep on the alert for slow-moving or quit vehicles. Sluggish down much more when you watch red taillights ahead. Protect against using your risk lights while moving — other vehicle drivers may think you’ve stopped. Use the appropriate edge of the road, white fog heat or roadside reflectors together a guide to remain in her lane. be patient. Don’t adjust lanes or pass other vehicles unless you really have actually to, and NEVER try to pass long lines of web traffic in fog. Don’t creep along; someone else may crash into you. If visibility is incredibly poor, exit the freeway or uncover a safe place to pull over. Part highways in California have actually signs that estimate roadway visibility and a 3-2-1 countdown sample of reflective pavement markers to aid motorists take leave ramps in heavy fog. If you need to stop and also there’s no surrounding exit, pull off the pavement as far as safely possible. Turn off your lights, collection the emergency brake and take your foot turn off the brake to be certain your taillights aren’t lit up. Rotate on her emergency flashers. Wait it the end until problems improve. Never stop in the travel lanes. If you can’t traction over, go slow and sound the horn occasionally.What You should Know around Fog Lights

Fog lights space designed come be offered at low rate in fog, hefty mist, snow and also other poor-visibility situations. They’re different from daytime running lights. They space an extra pair the lights placed low on the vehicle, v the thinking that fog doesn’t settle on the road surface however hovers 12 to 18 inches above it. They aim light into this layer of fog-free air. Lock also suggest to the right enough that the driver have the right to see the solid, white “fog line” in ~ the road edge together a guide.

Photo: Oregon room of transportation

The rule on making use of auto fog lamp — additionally known as fog lamps — differ by state. The key thing come know: friend can’t usage fog lights in a way that creates glare for other drivers. They have to be pointed and used so they won’t interfere v visibility for another driver within 25 feet. Below are specifics.

Basic Fog light Rules because that Western StatesCalifornia No much more than 2 fog lamps are permitted for highway driving. They may be used with, not instead of, your regular headlights. Fog lights need to be in a white to yellow color spectrum. You can’t have an ext than 4 sets that the following types lighted in ~ one time: Low-beam headlights High-beam headlights Fog lights Warning lamp Spot lamp Gaseous discharge lamps If friend pull end on the shoulder of the road, or space in stand traffic, you have to dim her fog lamps. None of your auto lights can produce glare in the eye of one oncoming driver within 500 feet. Because that off-highway driving, a car can have a max eight lamps for use as headlights when the automobile is operated off-road. Whenever the automobile is ~ above a highway, the extra lights should be rotate off and covered through an opaque hood.Colorado Headlights and other white lamps are minimal to a complete of four. Fog lights must be non-glaring. They have to be white, amber or any type of color in in between white and amber. Fog lamps may be used with but not rather of low-beams. None of your vehicle lights can create glare in the eye of an oncoming driver in ~ 500 feet.Idaho two front-mounted fog lamps room allowed. They might be supplied with low-beam headlights. Your fog lights can’t develop glare in the eye of oncoming drivers. This way no part of the main beam deserve to strike the human body of a person, vehicle, screen or other object higher than the fog desk lamp centers 25 feet or more ahead. Headlights must be ~ above in the daytime when vision is decreased to 500 feet or less.Montana two fog lights offering a low, wide-angle irradiate pattern room allowed. Fog lamps might be offered with her low-beams so lengthy as they don’t project a more powerful beam than your constant headlights. Castle can’t be provided as a substitute because that your continual headlights. None of the high-beam section of the left light can project much more than four inches over the facility of the lamp at a distance of 25 feet.Nevada two front-mounted fog lamps space allowed, and also may be used with your low-beams. No an ext than 4 auxiliary lights (like fog lights, high-beam lights, spot lights) might be lit at as soon as if any type of project a beam of 300 candlepower or more. No one of the high-beam portion of the left light can project an ext than 4 inches over the facility of the lamp at a distance of 25 feet.Oregon Fog lights need to be provided like your high-beams: rotate off as soon as within 500 feet of an oncoming vehicle and within 350 feet when following one more vehicle. Forward-pointing fog lights must be white, amber or yellow. Rear-mounted fog lights need to be red. Fog lamp must have a different switch from constant headlights. Fog lights may not be used rather of headlights. After-market fog lights have to meet federal rules. Assets must it is in labeled; anything that is labeled “not for street use” can’t be used on windy roadways.Utah two fog lights room allowed. No red or blue lights mirroring toward the front room allowed. No much more than 2 extra steering lights room allowed.Washington A max that two, front-mounted fog lights space allowed. They can only be offered with low-beams, not your high-beam headlights. They should be white or amber. No much more than four lights can shine to the front in ~ once. None of the high-beam part of the left light can project more than 4 inches over the center of the lamp at a street of 25 feet.

Each year, over 38,700 auto crashes occur in fog. End 600 people are eliminated and more than 16,300 world are hurt in these crashes annually. Treat low visibility driving through respect.

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Get an ext winter steering how-tos in ours ebook 19 Winter Driving resources You Can’t do Without. View real-time road problems for Western claims here.