How to Deal with Fogging on the Outside of Car Windows on Rainy Days?

[DeThomas]

When car windows fog up on rainy days, the following methods can be used to address the issue: 1. Preventive measures such as applying anti-fog spray. Spray a small amount of anti-fogging agent on the car windows and wipe it clean to remove dirt and stains from the glass. 2. Air conditioning cooling method. Utilize the air conditioning's dehumidification function to reduce air humidity and eliminate fog. 3. Air conditioning heating method. Use the method of reducing the temperature difference to remove condensation. Fogging on car windows during rain occurs under two conditions: high humidity and low temperature. When the air humidity is at a certain level and the window temperature falls below the dew point, condensation forms on the window surface, which is the fogging phenomenon we often see on the windshield. Additionally, when there is a certain temperature difference between the two sides of the window, and the saturated vapor pressure of the surface moisture on the cooler side is lower than the surrounding environment's vapor pressure, moisture gathers on the glass surface, forming tiny droplets that appear as fog. If the dew point is above zero degrees Celsius, fogging occurs; if it is below zero degrees Celsius, frost forms.