Slippery When Wet Sign

Updated July 9, 2026

Slippery When Wet · MUTCD W8-5 · Warning sign

What the Slippery When Wet sign means

This yellow diamond shows a car with wavy skid marks behind its tires, warning that the road becomes slippery when wet. Rain, ice, or an oily buildup can sharply reduce traction here — on bridges, shaded curves, or worn pavement. Slow down, increase your following distance, and avoid sudden braking, sharp steering, or hard acceleration that could break traction. The first rain after a dry spell is especially dangerous as oil rises to the surface. Smooth, gentle inputs keep the tires gripping in these conditions.

What to do when you see it

Slow down, leave extra following distance, and steer and brake gently to avoid skidding on the wet surface.

On the CA permit test

The skidding-car diamond warns the road gets slippery when wet — slow down and avoid sudden moves.

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