What to Do When the Front Windshield Fogs Up on Rainy Days?
2 Answers
Here are some methods to deal with fogging on the front windshield during rainy days: 1. Turn on the heater directly: Increase the fan speed, and the dry, warm air will evaporate the water molecules in the car's interior air, preventing fog from forming on the windshield. However, this method has a drawback: when the windshield starts to frost, turning on the heater raises the water temperature, and since water molecules cannot be removed in time, the fog on the glass often increases initially. But don't worry—once the overall temperature rises, the fog will disappear. 2. If the rain isn't heavy, you can open the windows slightly for a few seconds to help clear the fog: The principle is to lower the interior temperature, making it harder for moisture to condense. This method is generally more effective in winter because the air is drier, and opening the windows can help remove moisture from the car. However, on rainy days when the outside air is more humid, it may take longer. 3. Turn on the car's defroster directly: This is the simplest way to remove fog. The principle involves blowing dry, cold air from the car's interior onto the front windshield, equalizing the temperature inside and outside the glass and creating a dry air barrier. This prevents condensation of humid air inside the car and stops fog from forming.
I've been driving for years, and foggy windows on rainy days are a common occurrence. As soon as I get in the car, I turn on the air conditioning in windshield defogging mode. I'm used to using warm air in winter or cool air in summer, and the fog clears up right away. Don't rush to drive fast—it's very dangerous when you can't see the road clearly due to fog, so I maintain a steady speed. I always keep a dry cloth in the car for emergency wiping. High humidity easily causes fogging, so I avoid opening windows for ventilation on rainy days. Regularly cleaning the windows and air conditioning system can reduce the frequency of fog formation. I've maintained this habit for over a decade—safety comes first, and there's no need to rush.
