Driving guide

Driving in Rain: Hydroplaning and Wet-Road Technique

Rain doubles the crash risk of a typical drive. Most of the extra risk is from two related problems: longer stopping distances and the loss of traction during hydroplaning. Both are manageable if you change technique before things go wrong.

Slow down before you have to

Drop your speed below the posted limit at the first sign of rain. Wet pavement reduces tire grip by 30 to 50 percent. Increase your following distance from three seconds to four or five. If conditions are heavy enough that you can barely see the lane, find a safe place to pull off until visibility returns.

Hydroplaning

Hydroplaning happens when a film of water lifts the tire off the road surface. You feel the steering go light and the engine sound rises slightly because the wheels lose load. The fix is counterintuitive: take your foot off the gas, do not brake, do not turn the wheel sharply. Wait for traction to return as the tires slow.

Wipers and headlights

Most states require you to turn on your headlights any time your wipers are on. The point is visibility to other cars, not your own. If your wiper blades streak, replace them — about $20 of replacement blades is among the highest-value safety upgrades you can make.

Standing water and puddles

Avoid driving through standing water deeper than the bottom of your bumper. A foot of moving water can carry away a small car. After driving through a deep puddle, gently tap the brakes a few times to dry them — wet brake pads can take several seconds to engage.