Even the slightest bit of rain can be dangerous.

Before motorists have to deal with snow in the winter, they’ll encounter more wet conditions in the fall. Rain can cause surfaces to become slick, especially near intersections, particularly after it has been dry. Rainwater can mix with oil and other vehicle fluids that have leaked into the pavement.

Driving.ca notes that even with good tires, braking on wet pavement is about half as effective as dry. If, for example, a child darts out between cars in a residential area, or a car or pedestrian cuts across your path, a vehicle travelling at 48 km/h will require 37 metres to stop when it’s wet,  about the length of three school buses. Reducing that 48 km/h to 32 km/h cuts the stopping distance by more than half to just 18 metres. Even a little slower is safer.

Driving in a downpour has obvious risks, but a study published in the journal Bulletin of the American Meteorological Society highlights how even light precipitation can increase the dangers. The results found during precipitation there is a 34% increase in overall risk of a fatal car crash occurring. The risk was worse during winter and the morning rush hour.

Researchers analyzed past radar data to identify what the weather was at the recorded time and location of 193,840 reported fatal crashes from across the U.S. during a 5 year period. They found the risk increased by about 26% and 146% for their classifications of light and heavy precipitation, respectively.

Remember, speed limits are set for ideal conditions, not for when it’s raining. Driving safely means slowing down.

Michelin Canada offers drivers some tips on how to deal with rain when behind the wheel.

“Wet weather doesn’t receive the same attention as winter weather but it should,” the tire company’s website says. “Wet roads present similar dangers – less grip and longer stopper distance, for example.”

Michelin advises:

• Make sure your tires offer the proper amount of tread.
• Drive with two hands, always.
• Slow down before turning and maintain a consistent speed throughout the turn.
• While turning, don’t make any sudden steering wheel movements.
• Only brake in a straight line before the turn and do so gradually. Be careful if you need to brake during the turn.
• Increase your following distance from other cars significantly.
• If hydroplaning, do not accelerate or brake suddenly. Keep your foot lightly on the gas and steer the car forward until your tires regain traction.

What is hydroplaning?

Heavy rain can create puddles or standing water on the road, increasing the risk of hydroplaning. When this occurs the tires slip and do not respond to steering, braking or accelerating meaning water between your tires cannot be removed quickly enough. This layer of water builds up in front of the tire and loses contact with the road.

To regain control, don’t hit the brakes suddenly and ease off the gas gently until you slow down and gain traction. If you keep your foot on the gas, your vehicle could move in the wrong direction when your wheels regain traction.

How to avoid it:

• Check your tire pressure monthly. Pressure below 30% of what is recommended greatly increases the risk of hydroplaning.
• Check your tread depths monthly on all of your tires.
• Reduce speed when approaching large puddles or standing water

Rain also reduces visibility. The Official Ministry of Transportation Driver's Handbook recommends motorists:

• Drive slowly enough to be able to stop within the distance you can see. Remember, water can make brakes less effective.
• Ensure windshield wipers are in good condition. If your wiper blades can't clean the windshield without streaking, replace them.
• Try to drive on clear sections of road, looking ahead and planning your movements. Smooth steering, braking and accelerating reduces the chance of skidding. 
•  Leave more space between the vehicle ahead of you in case you need to stop. 
• Avoid driving in puddles which can hide potholes and can damage your vehicle or flatten a tire. 

Sometimes an accident happens, even when you've done everything you can to prevent it. In the event of a mishap, call police and your insurance broker for immediate assistance.