Curve Ahead Sign
The curve ahead sign is a diamond-shaped yellow warning sign with a black arrow showing a curve in the road. Unlike the winding road sign that shows multiple curves, this sign warns of a single curve ahead. The arrow bends in the direction of the curve — left or right — so you can prepare for which way you'll need to steer. Curve signs come in different styles depending on how sharp the curve is: a gentle curve shows a slight bend, while a sharp curve or hairpin turn shows a more dramatic angle. These signs are often accompanied by advisory speed plates that recommend a safe speed for navigating the curve. The recommended speed is calculated for typical conditions — in rain, ice, or when towing, you should go even slower. When approaching a curve, slow down before you enter it, not while you're in it. Braking in a curve can cause your vehicle to skid, especially on wet roads. Position your vehicle toward the outside of your lane as you enter the curve. Look through the curve to where you want to go, and maintain a steady speed through the turn. Curves are among the most common locations for single-vehicle run-off-road crashes.
Rules & What to Do
Slow down before entering the curve. Follow the advisory speed if posted. Stay in your lane — do not cross the center line. Look through the curve to where you want the vehicle to go. Accelerate gently only after you can see the road straightening out.
Penalties
No penalty for the warning sign itself. However, exceeding the advisory speed on a curve and losing control can result in citations for driving at an unsafe speed ($100-$300) or reckless driving. If you cross the center line, you may be cited for improper lane usage.
For Commercial Drivers
Curves are extremely dangerous for commercial vehicles due to their high center of gravity. Loaded trucks can roll over on curves at speeds well below the advisory speed. As a rule, reduce speed to below the advisory speed — the advisory is designed for passenger vehicles, not commercial trucks. Watch for off-tracking: your trailer will cut to the inside of the curve, potentially crossing lane lines or hitting barriers.
Frequently Asked Questions
What does a curve ahead sign mean?
A curve ahead sign warns that the road curves in the direction shown by the arrow. Slow down before the curve begins, stay in your lane, and navigate the curve at a safe speed.
What is the difference between a curve sign and a turn sign?
A curve sign indicates a gradual change in road direction, while a turn sign warns of a sharper change. Turn signs indicate you'll need to slow down more. Both may be accompanied by advisory speed plates.
What does the yellow speed sign below a curve sign mean?
The yellow speed plate below a curve sign is an advisory speed — it recommends a safe speed for the curve under good conditions. It's not a speed limit, but exceeding it is risky. In bad weather, go even slower.