How to Remove Fog from the Windshield on Rainy Days

[JosiahLee]

When the windshield fogs up on rainy days, the following methods can be used to remove the fog: Turn on the defroster in the car: Activate the defroster while also pressing the compressor (A/C) button. This will lower the temperature inside the car, which may feel cold in autumn and winter, but the defogging effect is noticeable. Turn on the warm air from the air conditioner: Increase the fan speed. The dry, warm air will evaporate the moisture inside the car, preventing fog from forming on the windshield. Purchase dry anti-fog wipes: Before using dry anti-fog wipes, first wipe the windshield with a damp cloth or use them directly when fog appears. After wiping, the windshield will remain fog-free for up to 24 hours. Purchase wet anti-fog wipes: Wipe the fogged areas directly. After wiping, the windshield will remain fog-free for up to 24 hours. Purchase anti-fog spray: Spray the glass anti-fog agent directly onto the windshield. The anti-fog effect typically lasts around 10 days, with high-quality products even lasting up to a month, far outperforming anti-fog wipes.

[VanWyatt]

The most annoying thing when driving in the rain is the fogging on the windshield. I've figured out a simple and effective method: don’t rush to turn on the AC when you get in the car. First, turn on the external circulation to balance the temperature inside and outside the car. Then, press the AC button, lower the temperature slightly, and turn on the windshield defogger. Here’s the key—increase the fan speed to blow air onto the windshield, and the fog will clear up quickly. Avoid just using the heater or relying solely on the wipers, as that will only make it worse. Also, keeping a dry towel handy to wipe the inside of the glass is quite convenient, but don’t get distracted while driving. For long-term maintenance, regularly replacing the cabin air filter can reduce the chances of fogging.

[Alfie]

Bro, let me teach you a budget trick! I mix dish soap with water at a 1:10 ratio to wipe the inside of the glass. Once dry, it forms an anti-fog film, costing less than two bucks. But for emergencies, rely on the AC: first press the defog button with a fan and arrow (usually on the left side of the dashboard), immediately turn on the AC for cooling, and remember to switch to external circulation! A detail many overlook—if fog condenses into water droplets, adjust the temperature to about 5 degrees higher than outside for it to work. Also, don’t forget to turn on the rearview mirror heating button. For foggy side rear windows, press the square button with waves. If there are many people in the car, crack the window a bit for faster air exchange.

[McRylee]

From a physical perspective, defogging addresses two issues: temperature difference and humidity. My routine involves four steps: 1. Press the MAX defog button immediately after starting the car to force ventilation; 2. Set the temperature around 22°C to balance the inside and outside temperature difference; 3. Always turn on the compressor (AC button) for dehumidification; 4. Finally, switch back to automatic air conditioning mode. Be careful not to block the windshield vents with phone holders, and closing the central vents during defogging can enhance airflow. Keep an anti-fog spray in the glove compartment—one application lasts about two weeks. It’s also important to break the habit of drinking hot beverages in the car!

[DallasRose]

Last week, while driving my child to school, we encountered a heavy rainstorm, and the windshield instantly became foggy. I immediately turned on the hazard lights, pulled over, and pressed the fan-shaped button with three arrows on the AC panel (the rear window defroster button is next to it). I turned the temperature knob to the blue zone and set the fan speed to level four. I waited until the rearview mirror was clear before continuing the drive. Now, I'm teaching my daughter to recognize these buttons: the fan-shaped one is for the front windshield, the square one is for the rear windshield, and the AC light must be on for them to work. On rainy days, it's best to leave ten minutes earlier than usual in case heavy fog requires extra time to handle. When the humidity inside the car is high, avoid leaving wet umbrellas directly on the seats.