How to prevent your car's windshield from fogging in the rain

Driving in heavy rains can be quite dangerous, especially when visibility is almost down to zero. In order to have a good view of the road during the rainy season, you definitely need a fog-free windshield. 

Condensation happens when water vapor comes into contact with a surface that is colder than the ambient temperature. Any vapor that comes into contact with the said surface will liquify causing the surface to fog up. You may even notice this on a sunny day. With enough humidity and an AC vent pointed at the window of your car, some condensation will form given that ambient temperatures are not too hot. That said, there are several ways on how you can prevent fogging on your windshield when it’s raining, just follow these simple steps.

The moisture buildup could happen in or out of your car’s windshield. It actually depends on the temperature, if it’s a cold day and your car’s cabin is hot, then the moisture will build up inside. Whereas, if it’s a hot day and your car’s cabin is cold, the moisture will form outside of your windshield. 

• Clean your windows regularly - One of the best ways to avoid this is to clean your windshield regularly in order to remove the dirt and oil particles which serve as moisture magnets. You can use a microfiber cloth along with water and other glass cleaning solutions which should bring back the transparency of your glass. 
• Apply anti-fog products - It’s easy to apply and you can buy it in automotive and hardware shops. You’re just going to have to spray it on the windshield and wipe it off, and it should work fine already. The anti-fog should be applied after you’ve thoroughly cleaned your windshield with your glass cleaning solution.
• Check your car’s weatherstrips - The rubber gaskets on your doors and windows are known as weatherstrips, and it can deteriorate overtime. Once that happens, moisture may seep through and enter your cabin. 

If you happen to find any damp spots on your upholstery after parking or driving in heavy rain, then you might want to have your car’s weatherstrips checked in order to find out if it’s already in need of a replacement.

Now, if you happen to experience fogging on your windshield while driving in the rain, you can actually get rid of it through performing the following tips and tricks below. 

• Wipe your windshield - First up, is you wipe your windshield with a clean, dry, and lint-free cloth. Before doing so, just make sure that your vehicle is in a complete stop as it would be dangerous to do this while your car is in motion. 
• Activate your front window defroster - Your car’s front defroster has vents on the dashboard that face the windshield. The fan and blower motor that operate the heating and air conditioning will also circulate air through the said vents in order to defrost the windows. 
• Adjust the temperature of your air conditioning system - You should also try matching your A/C system with the outside temperature. Anecdotally, the throughput might still be a bit cooler, although doing this will still help. 

If that doesn’t work, then try to lower the temperature of your A/C as many experts recommend using cool air to lower the temperature on the inside of the glass, therefore, allowing the moisture buildup on your windshield to stop.

Probably, the thing you see on your windshield is not entirely moisture, as it could be mixed with oil, therefore, making it a hard smudge to remove. If you’re wondering how it turned out to be like that, the oil could come from a cleaning solution or maybe from an air freshener you have in the car. Removing this stubborn oil should be easy, just rub the affected area with alcohol or soda using a soft cloth.