What to Do When the Windshield Fogs Up on the Outside During Rainy Days?
4 Answers
Solutions for fogging on the outside of the front windshield during rainy days: 1. You can use the windshield wipers or spray windshield washer fluid, which contains surfactants that can delay fogging. 2. The fastest and most effective method is to adjust the air vents to the front windshield, turn on the air conditioning cooling function, and activate the external circulation. Using the maximum fan speed, it only takes about ten seconds to quickly "blow" away the fog on the glass. Here are three methods to prevent window fogging: (1) Spraying Anti-Fog Agents and Other Preventive Measures: Spray a small amount of anti-fog agent on the car windows and wipe it clean to remove dirt and stains from the glass. While polishing the glass, it forms a thin transparent protective film that effectively prevents water vapor from condensing into fog on the glass, especially suitable for cold winters. Alternatives to anti-fog agents include dishwashing liquid, soapy water, glycerin, alcohol, or saltwater. After drying, use chamois or a soft dry cloth to remove excess fibers, ensuring the car windows remain fog-free for several days. (2) Air Conditioning Cooling Method: Use the air conditioning's dehumidification function to reduce air humidity and remove fog. Turn on the air conditioning to blow cold air toward the front windshield, utilizing the dehumidification feature to quickly remove fog. If humidity is too high and the air conditioning is ineffective, slightly open a window to rapidly reduce the humidity inside the cabin. (3) Air Conditioning Heating Method: Use the method of reducing temperature differences to eliminate fog. In winter, blow warm air onto the glass to quickly raise the temperature of the front windshield, reducing the temperature difference between the inner and outer surfaces of the glass, thereby preventing excessive fogging. However, note that the rear and side windows heat up more slowly, requiring more time to remove all fog.
I'm all too familiar with the situation where the windshield fogs up on the outside during rainy days. It's mostly caused by the air conditioner's cold air blowing directly onto the glass. My first move is always to turn on the wipers for a few swipes, which clears it up immediately. If the fog keeps coming back, I adjust the direction of the air vents to avoid direct airflow onto the windshield. If I have anti-fog spray with me, I apply some to the outside of the glass beforehand—it works like a charm. Safety comes first on rainy days, so I never dare to distract myself by manually wiping the windshield in such situations—it's just too dangerous. Regularly replacing worn-out wiper blades is also crucial; good blades clear the glass with a single swipe. If all else fails, I pull over safely, turn on the hazard lights, and deal with it properly before moving on. Never take the risk of driving with a foggy windshield.
In rainy weather, fogging on the outside of the windshield is most common, mainly due to the low external temperature and the cold air from the car's AC causing condensation on the glass surface. The first thing I do is turn on the wipers to clear the fog, while adjusting the AC vents to blow towards the body or feet, avoiding direct cold air onto the glass. If the car has a rearview mirror heating function, turning it on can also help a bit. It's important to remind myself to regularly check the condition of the wiper blades; if they're old and have lost their elasticity, replace them promptly, otherwise they'll just make the view blurrier. Driving safety is inherently lower in rainy conditions, so when visibility is poor, I proactively reduce speed, increase following distance, and stay focused even when using the defogging function, ensuring it doesn't distract too much from driving.
If the windshield fogs up on the outside, simply turn on the wipers—quick and easy. For recurring fogging, adjust your AC settings by lowering the temperature or redirecting the vents away from the glass. Pre-treating the glass with soapy water and wiping it dry can also help prevent fogging. Keeping an anti-fog spray in the car is even more convenient—one application lasts a while. Good wipers are essential; replace worn rubber blades early. Safety comes first in rainy weather—drive slower or pull over if visibility drops, never push through blindly.
