4.2 Fog, Rain, Snow, Ice & Winter Emergency Kits

Driving in Fog

Fog brings unique challenges that require extra care. The manual's guidelines:

• Reduce your normal driving speed.
• When you see headlights or another vehicle's taillights ahead, reduce your speed even more, and be prepared to stop quickly.
• Use low-beam headlights only, plus fog lights if you have them. High beams reflect off the fog and blind you.
• If the fog is so thick that you cannot safely drive, pull completely off the road to a safe location and turn on your emergency flashers. Do not stop in a travel lane.

Keep the right edge line in view as a guide, and listen for traffic you cannot yet see.

Inclement Weather and Traction

Traction is the grip between your tires and the road that lets you start, stop and change direction. Wet roads reduce traction, and risk rises further when roads are covered with snow or ice. The manual stresses thinking ahead and acting early instead of just reacting to other drivers. In bad weather:

• Keep a safe distance. The space you need is much greater on wet roads than on dry roads, and even greater on snow or ice.
• Reduce your speed so you have more time to react.
• Make sure your tires have good tread under the manufacturer's recommendations.
• Avoid slamming on your brakes, which can make you skid. If your vehicle does not have an anti-lock braking system, pump the brakes to prevent skidding.
• Avoid jerking the steering wheel or changing speed quickly.
• Make sure your windshield wipers work well, and use your headlights. Maryland requires them when your wipers run continuously.

Rain is most slippery when it first starts, because water lifts oil and grime off the pavement. Slow down at the first drops, and remember that hydroplaning becomes more likely as speed and standing water increase (see Section 4.3).

Driving on Snow and Ice

The manual says there is no such thing as a "completely safe" speed on ice and snow. Every road can differ with sun, shade and the amount of salt. Key points:

• Black ice is a thin, nearly invisible layer of ice on blacktop. It forms when ice or snow melts and refreezes, and it can cause a crash if you are not aware of it.
• Ramps and bridges freeze before roads. Plowed roads may refreeze at night or have icy patches from snow that melted during the day.
• Four-wheel-drive vehicles can also slide. Four-wheel drive helps you get moving; it does not help you stop.

The manual's snow and ice suggestions:

1. Slow down. Nothing makes it safe to drive on ice or snow-covered roads at normal speeds.
2. Keep windows and lights clear. Remove all ice and snow from your vehicle before driving.
3. Start very slowly, then test your brakes gently to learn how well you can stop.
4. Start slowing long before an intersection or turn.
5. Keep your gas tank and windshield-washer fluid full.
6. Use chains, snow tires or radial tires on designated snow emergency routes when a snow emergency is declared.

Your Winter Emergency Kit

The manual says to keep an emergency kit in your car containing:

Preparing the Vehicle for Bad Weather

Before winter, check tire tread and pressure, wiper blades, washer fluid, defroster, heater and all lights. Before each trip in snow, clear the windshield, all windows, mirrors, lights and the roof, and give the defroster time to work.

Putting the Rules Together

Scenario 1 (fog): Visibility drops to almost nothing on a rural road. Slow down, keep low beams on, and if you still cannot see, pull completely off the road into a lot or driveway and turn on your flashers.

Scenario 2 (bridge in winter): The road has been fine, but a bridge is ahead and it is 30 degrees. Ease off the gas before the bridge, keep the wheel steady and avoid braking on the bridge deck.

Scenario 3 (older car without ABS): Your wheels start to lock while braking on snow. Pump the brakes, as the manual advises for vehicles without anti-lock brakes, and steer smoothly.

Exam Traps

• Fog equals low beams, never high beams.
• Bridges and ramps freeze first.
• Four-wheel drive does not shorten stopping distance.
• Pumping the brakes is for vehicles without ABS; with ABS, press firmly and hold (Section 4.3).