Any time you drive, you are likely to spot anywhere from a few to over a dozen different warning signs. Despite learning the most common warning signs for driving, every new driver will at some point come upon a traffic warning sign they simply have no clue about. It’s worth taking a moment to read up on the signs you are unsure about.
If you prefer video, we’ve created one with driving instructor Jacqueline. She will drive along a route filled with important road signs and explain what to look for and what they mean.
Warning Signs Are Very Important to Know as a Driver
Why? Because warning signs are used to alert drivers to an unexpected or dangerous road condition or traffic situation. This means it can be dangerous to misunderstand a warning sign. Traffic warning signs are usually yellow or orange with black symbols on a diamond-shaped or rectangular sign.
Below are the 50 Most Common Warning Signs in the United States. Most other warning signs are variations of these.
Curves and Turns
Turn (Left/Right). This sign indicates a sharp turn in the direction of the arrow ahead. Slow down and proceed with caution.
Turn With Advisory Speed Limit. This sign indicates a sharp right turn ahead. The advisory speed limit for this curve is 25 mph under ideal conditions.
Curve. This sign indicates that the road ahead will curve to the left.
Curve with Advisory Speed Limit. This sign indicates that the road will curve to the right. The advisory speed limit for this curve is 35 mph under ideal conditions.
Reverse Turn (First Turn to the Left). This warning sign indicates that there is a reverse turn ahead. In this case, there is a sharp turn to the left and then to the right.
One Direction Arrow. This sign indicates that you are only allowed to travel in the indicated direction. In this case, to the left.
Two Directional Arrow. This sign indicates that you are not allowed to go straight ahead. You must turn either left or right.
Reverse Curve (First Curve to the Left). This warning sign indicates that there is a reverse curve ahead. In this case, the road curves to the left and then to the right.
Winding Road. This sign indicates a series of curves ahead. In this case, the first curve is to the right.
Hairpin Curve. This sign indicates a hairpin curve ahead. A hairpin curve is a very sharp curve that often completely reverses your direction of travel.
270-Degree Loop. This warning sign indicates a 270-degree loop ahead. Slow down and prepare for a very sharp turn.
Chevron Alignment (Left). This sign indicates that the road will change direction sharply. Slow down to a safe speed.
Main Road Curves to the Right Ahead. This sign indicates that the main road curves right with a side road entering from the left side in the curve.
Intersections
Crossroads. This road sign indicates a crossroad ahead. Slow down and prepare for traffic coming from all directions.
Side Road at Perpendicular Angle. This sign indicates there’s an upcoming side road at a T-intersection. Be prepared for traffic entering the road from the side road.
Side Road at Acute Angle. This warning sign indicates there’s an upcoming side road at an acute angle. Be prepared for traffic entering the road from the side road.
T-Roads. This sign indicates that the road you are traveling on is about to end, and that you must turn left or right.
Y-Roads. This road sign indicates that the road is about to split into two different directions. Be alert for other vehicles changing lanes.
Double-Side Roads. This sign indicates there will be double-side roads on the left side. Be prepared for traffic entering the road from the side roads.
Circular Intersection Warning (Roundabout). These warning signs indicate a roundabout ahead.
Advance Traffic Control
STOP Ahead. This sign warns that you are approaching a STOP sign. Slow down and prepare to come to a complete stop!
Yield Ahead. This sign warns that you are approaching a Yield sign. Slow down to a speed at which you can yield if necessary.
Speed Limit Ahead. This warning sign indicates that you are approaching a reduced speed zone. In this case, the speed limit ahead is 45 mph.
Traffic Signal Ahead. This sign warns of traffic signal ahead. Be prepared to stop if the lights are red or yellow.
Lanes and Merges
Merge (Right). This sign indicates that traffic from the right will merge ahead. Be prepared for vehicles entering your lane!
Merge (Left). This road sign indicates that traffic from the left will merge ahead. Be prepared for vehicles entering your lane!
Right Lane Ends. This warning sign indicates that the right lane ends ahead. Vehicles traveling in the right lane must merge left.
Added Lane (Via Merge). This sign indicates that merging traffic can continue in an added lane, and that merging movement will not be needed.
Narrow Bridge Ahead. This sign warns of a narrow bridge ahead. The bridge is narrower than the road you are driving on, so you may need to yield to wide vehicles on the bridge.
Divided Highways
Divided Highway. This warning sign indicates a divided highway. The traffic lanes ahead are divided by a median/divider.
Divided Highway Ends. This sign indicates the end of a divided highway. The traffic lanes ahead will no longer be divided by a median/divider.
Two-Way Traffic. This sign warns of two-way traffic ahead. It’s often shown when you are leaving a separated one-way road and entering a two-way road.
Hills and Grades
Steep Grade/Hill. This warning sign warns of a steep downgrade up ahead on the road.
Dip. This sign warns that the road goes down abruptly (dips) in the road ahead. Slow down to prevent damaging your vehicle.
Pavement Ends Ahead. This sign indicates that the pavement ends ahead. The road will likely turn into a gravel or dirt road.
Road Slippery When Wet. This warning sign indicates that the road ahead is slippery when wet. Adapt your speed to the conditions when you come upon this sign.
Rail and Light Rail
Railroad Crossing Ahead. This sign is posted before most railroad crossings. Slow down to a speed at which you can safely stop, and be alert for a train.
Railroad Intersection Warning. This sign indicates a railroad crossing just after/before an intersection ahead.
Low Ground Clearance Railroad Crossing. This sign indicates that the railroad crossing is slightly raised compared to the road. Low ground clearance vehicles may get stuck while trying to cross.
Emergency Vehicles
Fire Station. This sign indicates a nearby fire station.
Bicycles
Bicycle Crossing. This sign warns of a bicycle crossing ahead.
Pedestrians, Rail and Aviation
Pedestrian Crossing. This sign warns of a pedestrian crossing ahead
Animals
Deer/Cattle Crossing. These signs warn of a deer/cattle crossing ahead. Stay alert for deer/cattle suddenly entering the road.
Low Clearances
Low Clearance. This sign indicates you are approaching an overpass. There is 12 feet 6 inches of clearance from the road to the overpass.
Advisory Speeds
Speed Advisory. This sign indicates an advisory (recommended) speed for the road ahead under ideal conditions.
Exit Speed Advisory. This sign indicates an advisory (recommended) exit speed under ideal conditions.
No Passing Zone. This sign indicates that passing is prohibited within the zone ahead.
Hazard Marker. These signs are usually placed on or near objects close to the road. The sign varies depending on which side of the road the object is located. In this case, you should drive on the right side of the sign.