How to Drive Safely in Difficult Conditions - Step-by-Step Tutorial

Different weather and road conditions require specific techniques for safe commercial driving. This tutorial covers how to handle night driving, fog, winter weather, and hot weather—including the key procedures frequently tested on the CDL exam.

Difficulty Level: Intermediate
Time Required: 20 minutes to understand concepts
Prerequisites: Basic commercial vehicle operation knowledge

Step 1: Adjust for Night Driving

Know Your Visibility Limits

Rule: Drive slowly enough to stop within your headlight range.

Proper Headlight Use

1. Use high beams when safe—they double your visibility
2. Dim within 500 feet of oncoming vehicles
3. Dim within 500 feet of vehicles you're following
4. Don't retaliate if others don't dim—it increases danger

Avoid Glare

1. Don't look directly at oncoming lights
2. Look to the right—at lane marking or road edge
3. Keep windshield clean inside and outside
4. Keep interior cab lights dim
5. Don't wear tinted lenses at night

Combat Fatigue

Warning signs:

• Heavy eyelids, difficulty focusing
• Yawning repeatedly
• Can't remember last few miles
• Drifting from lane
• Missing exits

If you notice these signs:

1. Stop at the nearest safe place
2. Take a 15-20 minute nap minimum
3. Don't rely on caffeine—it's temporary

Critical: The only safe cure for drowsiness is sleep.

Step 2: Handle Fog Safely

Decision Point

Best choice: Don't drive. Pull into rest area until visibility improves.

If You Must Drive in Fog

Before entering fog:

1. Slow down BEFORE you enter
2. Turn on low beams (NOT high beams)
3. Turn on fog lights if equipped
4. Activate 4-way flashers

While in fog:

• Use roadside reflectors as guides for road curve
• Listen for traffic you can't see
• Don't pass other vehicles
• Don't assume fog will thin out
• Don't trust taillights ahead (vehicle may be off road)
• Don't stop on roadside unless absolutely necessary

Why low beams? High beams reflect off fog particles and actually reduce your visibility.

Step 3: Prepare for Winter Driving

Pre-Trip Winter Checklist

Fluids:

• Coolant level adequate
• Antifreeze tested for proper protection
• Windshield washer fluid full (use antifreeze type)

Equipment:

• Defrosters working
• Heater working
• Wipers in good condition, pressing firmly
• Chains available and checked for damage

Safety:

• Exhaust system checked for leaks (carbon monoxide danger)
• Windows, mirrors cleared of ice/snow
• Steps and handholds cleared

Identify Icy Conditions

Signs of ice:

• No spray from other vehicles' tires
• Ice on your mirrors or wiper blades
• Temperature near or below 32°F
• Bridges and overpasses (freeze first)

Remember: If mirrors and wipers have ice, the road probably does too.

Winter Driving Techniques

1. Start gently—get the feel of the road
2. Turn gently—sudden turns cause skids
3. Brake gently—don't brake harder than necessary
4. Turn OFF retarder/engine brake—prevents drive wheel skids
5. Increase following distance—you need more stopping room
6. Don't pass unless necessary—minimize lane changes
7. Watch for melting ice—wet ice is MORE slippery

Step 4: Dry Wet Brakes

When Brakes Get Wet

Driving through deep water causes:

• Weak braking power
• Uneven braking
• Grabbing brakes
• Possible jackknife

The Drying Procedure

While crossing water:

1. Slow down
2. Shift to low gear
3. Gently apply brakes (keeps water/mud out of brakes)
4. Increase engine RPM while maintaining light brake pressure

After exiting water: 5. Maintain light brake pressure for a short distance 6. This heats and dries the brakes

Test your brakes: 7. Check behind for following traffic 8. Apply brakes firmly when safe 9. If not working well, repeat drying procedure

Warning: Don't apply too much brake and accelerator together—can overheat brake drums.

Step 5: Handle Hot Weather

Tire Monitoring Schedule

In very hot weather: Check tires every 2 hours or 100 miles

Tire Pressure Rules

Why not release air? When tire cools, pressure will be too low, risking blowout.

Engine Monitoring

While driving, watch:

• Oil temperature gauge (stay in proper range)
• Coolant temperature gauge (stay in normal range)

If temperature goes above safe range:

1. Stop as soon as safely possible
2. Investigate the problem
3. Don't continue—risk of engine failure or fire

Adding Coolant Safely

If system has recovery/overflow tank: Can add coolant even when engine is hot.

If system has NO recovery tank:

1. Shut off engine
2. Wait until engine has cooled
3. Put on gloves or use thick cloth
4. Turn cap slowly to first stop—releases pressure seal
5. Step back while pressure releases
6. When pressure is gone, press down and turn cap to remove
7. Check level and add coolant if needed
8. Replace cap securely

Safety Test: If you can touch the radiator cap with bare hand, it's probably cool enough.

Step 6: Handle Aggressive Drivers

When Confronted

1. Get out of their way—your first priority
2. Don't challenge them—put pride aside
3. Avoid eye contact
4. Ignore gestures—don't react
5. If safe, call police with description and location

Don't Become One

• Accept delays calmly
• Don't drive slowly in the left lane
• Let others merge
• Keep hands on wheel—no gestures
• Give other drivers the benefit of the doubt

Common Mistakes to Avoid

Mistake 1: Using high beams in fog High beams reflect off fog and reduce visibility. Always use low beams.

Mistake 2: Releasing air from hot tires When tires cool, pressure will be too low. Never release air—just wait for tires to cool.

Mistake 3: Using retarder on ice Retarders and engine brakes can cause drive wheel skids on slippery surfaces. Turn them off.

Mistake 4: Driving through drowsiness Caffeine is temporary. The only safe cure is sleep. A 15-20 minute nap can save lives.

Mistake 5: Removing hot radiator cap Steam and boiling coolant can cause severe burns. Wait until system cools.

Frequently Asked Questions

Q: What's the low beam visibility range?

A: 250 feet. High beams give 350-500 feet. Adjust speed to stop within these distances.

Q: How do you know if the road is icy?

A: No spray from vehicles, ice on mirrors/wipers, temperature near 32°F, and you're on a bridge or overpass.

Q: How often to check tires in hot weather?

A: Every 2 hours or 100 miles. Never release air from hot tires.

Q: What lights in fog?

A: Low beams and fog lights. High beams make it worse.

Q: How to dry wet brakes?

A: Light brake pressure while crossing water, continue light pressure after to heat and dry, then test.

Q: What to do when drowsy?

A: Stop and sleep. A 15-20 minute nap is the only safe cure.

Quick Reference

Next Steps

1. Memorize headlight ranges: 250 feet (low), 350-500 feet (high)
2. Remember: low beams in fog, no retarder on ice
3. Know the wet brake drying procedure
4. Hot tires: never release air

Ready to test your knowledge? Start practicing with our Driving Conditions questions.