How to Avoid Hydroplaning in the Rain

Losing traction in your vehicle can be one of the most frightening feelings, as you temporarily lose full control and ability to maneuver the car. While this can happen in any road condition, weather plays the largest factor in your vehicle’s ability to gain traction. 

When rain hits the streets, it creates a thin top layer of water over the road surface and prevents your tires from creating the level of traction you’re used to. Upon the beginning of a rain storm, the grease and oils trapped within the asphalt are brought to the surface, making it even slicker for the first 10-20 minutes. These factors combined to make driving in the rain something that needs to be approached with caution and foresight. 

What is Hydroplaning?

Hydroplaning refers to a vehicle losing all available traction over a puddle or stream water. As the tires have no traction against the road, the driver of the vehicle essentially becomes the passenger for whatever physics decides to do until friction is regained. 

The feeling of hydroplaning is not a mistakable one, as you’ll experience a sudden jolt and feel the car begin to rotate or skid. The effect of hydroplaning is highly circumstantial, as your vehicle could either regain traction almost immediately over a smaller amount of water or continue skidding for the longest few seconds of your life over a larger one. The unpredictability and danger of hydroplaning are why proper wet-weather driving techniques are critical for any driver. 

Why Do Cars Hydroplane?

So why do your tires lose traction over water? Shouldn’t “all-season” or “all-weather” tires keep you safe in all weather?

If you’ve ever looked over your tire tread, you’ve likely noticed the various channels running all over the surface of the tire reminiscent of little canals, called “sipes”. These aren’t just shaped like aqueducts, that’s essentially what they are. As your tread runs over a wet surface, the channels allow for the water to be dispersed out of the sides of the tread. Contrast this to a completely smooth tire, where the water would become trapped between the tire and the road surface, creating a thin layer of water that prevents the tires from fully contacting the asphalt. 

When you hydroplane, it’s because the channels in the tire’s tread were unable to disperse that amount of water in time. This leads the tire to ride the surface of the water rather than the street, causing a complete loss of traction and control. 

While modern commuter vehicle tires have better water dispersion capabilities than ever before, that doesn’t mean they can take any amount of water at any speed. Even the best wet-weather tires will have a point where they can no longer move enough water to produce traction.

How Can I Avoid Hydroplaning?

Drive Slowly

This one is probably a given, but reducing your speed while driving in the rain can considerably reduce your chance of hydroplaning. Slower speeds allow the vehicle to remain under control over even large amounts of standing water. 

A good rule of thumb for speed in the rain is to take 5 MPH off the normal speed limit, although we’d recommend slowing down even further at highway speeds in severe rain. 

Keep an Eye on the Tire Tread

As stated earlier, the channels in your tire tread are responsible for dispersing the water away from the contact patch. As the tread wears down, so do the channels. This reduction in the height of the channels prevents them from moving as much water and increases the likelihood of hydroplaning. 

Tire wear is of course to be expected, but it’s crucial to keep an eye on the condition of your tread to avoid driving on balding tires that could cause your car to lose control. The US Department of Transportation recommends tires be replaced when the tread hits 2/32nds of an inch and is even legally required in certain states. 

An easy way to test tread depth is the penny method, which consists of taking a US penny, turning Lincoln’s head downwards, and placing it between the ribs of the tread. If the top of Lincoln’s head is covered by tread, your tires are still in useable condition. If the entirety of Lincoln’s head is visible, your tread is becoming unsafe and your tires need to be replaced ASAP.

Leave More Room Between Vehicles

When driving in dry weather, it’s easier to judge your needed distance for a smooth stop. This can lead to drivers developing a habit of following vehicles at that distance every time they drive. 

While that works fine on dry roads with plenty of traction, the reduced traction of a wet road will increase the distance your vehicle needs to stop safely. Not only that, but the lack of traction may cause drivers around you to unexpectedly lose control, putting you in a dangerous situation where a quick stop or maneuver is needed. 

For this reason, you should always be aware of your following distance and braking distance behind the cars around you. Giving yourself enough time to correct your own mistake or avoid somebody else’s is always the best way to stay safe when driving, but this is even more true in inclement weather like rain or snow. 

In general terms, it’s recommended to remain about 3-4 seconds behind the vehicle in front of you in normal conditions. However, in the rain, this distance should be increased to at least 5-8 seconds. 

Use Your Headlights

This one may not be directly tied to the traction of your vehicle, but it’s still a very important part of staying safe and visible to the drivers around you in bad weather. 

Using your headlights while it’s raining allows other vehicles to see you further in advance, and vice-versa. It may not be too dark out, but the reduced visibility and fog coverage of rain make judging the distance of other vehicles significantly harder. 

One important thing to remember is to only use low-beam lights in rain and fog, as the intense light of high-beams will reflect off the fog and moisture causing glare for you and others. 

Vehicle Inspections at Lake City Auto Care

If you’re looking for an in-depth inspection of your vehicle and its most important systems, trust the experienced technicians at any Lake City Auto Care store. We have four locations in Kootenai County, Idaho ready to ensure your vehicle is as safe as possible for you and your passengers. Give us a call or schedule online today to speak with our friendly and knowledgeable service advisors!