What signs indicate that the road is slippery?

The presence of ice formation, water pooling, or significant rain clearly indicates that the road may be slippery. Ice can create a dangerously smooth surface, making it difficult for vehicles to maintain traction. Similarly, pooling water can lead to hydroplaning, where tires lose contact with the road, resulting in a loss of control. Significant rain can also wash away road surfaces or create slick conditions, especially if the rain is heavy enough to combine with oil and debris on the road, leading to a hazardous driving environment.

In contrast, dry pavement with good visibility would typically suggest safe driving conditions. Foggy conditions might reduce visibility but do not inherently indicate a slippery road surface. Heavy traffic combined with light rain might create caution due to congestion, but it doesn't directly point to slipperiness unless accompanied by other factors like water pooling or poor drainage.