How to Keep Car Windows From Fogging Up in The Rain?

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How to Keep Car Windows From Fogging Up in The Rain?

Imagine waking up and getting prepared in a hurry to meet the report’s deadline in the office. Unexpectedly, it’s raining outside, but you are grateful there is no snow. After settling in the car and igniting the engine, you realize the fog is all over your window. You wipe it hurriedly using tissue on your dashboard. After a few seconds, it forms again. What a day! Remember, fog affects your visibility. If you dare drive with your windshield foggy, you can quickly get into an accident. Instead of cursing the day, begin by understanding why the windows are foggy.

The temperature outside is lower than the temperature inside the car. Fog formation takes place when different temperatures meet. That means, when the warm moist air in your car hits the cold windshield, the fog will form. Getting out with a rag to clean the window when it’s raining is useless. Maybe you’re wondering, where is this excessive moisture in your car coming from, and what’s the solution? The answers are right below.

What Causes Your Car To Have Excessive Moisture?

The easiest way to get the solution is first to identify the cause of the problem. Below are a few reasons that cause excessive moisture in your car.

Respiration from passengers

Look no further; you and the passengers are culprits causing the excessive moisture. Your respiration will cause moist warm air.

Wet items 

If your coat gets wet, you will probably remove it and put it in the car. The same case happens with a wet umbrella. Wet items will increase the moisture causing fog.

Water leakage

Maybe you came late at night and forgot to close the window well. If it rains, the water will find its way inside your car’s upholstery. If that’s not the case, your car could be having a dent somewhere that is leaking the water. Though your car is new, that doesn’t mean it can’t have a small factory fault. Could be, the factory failed to seal it completely.  It can also leak as a result of;

Poor Windscreen Replacement 

If you got an accident and took your windscreen to be replaced, that could be the problem. Did the mechanic replace it well or he did shoddy work. If he didn’t replace it well, it could be allowing excessive moisture right inside.

Heater core

Does the fog form immediately after you start your engine? The problem could be right there. One sign that the leakage is from the heater core is that it produces a sweet candy smell. It will also produce a green/orange fluid on the floor. Unfortunately, if the heater core is the problem, replacing it would be a worthy expense.

Damp Floor

A damp floor could also be another cause of excessive moisture. Either your shoes carried water due to rain, or there is snow.

Now that you know some of the causes of excessive moisture, below are ways you can deal with the fog.

Dealing With Fog When It’s Raining

The car windows fog up inside when it rains. It can be hectic trying to see the road well through the fogs and the raindrops. One way of removing the excessive warm moist air is by opening the window. Is that even advisable when it’s raining? No, it will allow excess water and worsen the problem. Knowing how to keep windows from fogging up when it’s raining is essential. You can buy a window cleaner from your local department store and use it to clean your windows. You will not struggle to deal with dirt and fog when it’s raining.

Removing Fog During Winter

Remember that the air outside is chilly, and the air inside the car is moist and warm. The tactic on how to stop car windows from fogging up in winter will help you. Below are a few steps to follow.

Change Your Air Source

Now that your car is new, have you familiarized yourself with it? Two buttons can help you deal with fog on your windscreen. Both buttons have a drawing of a little car. One has an arrow pointing outside while the other one has a circular arrow. Use the one with the arrow pointing outside to get air from outside. Pressing the button with the circular arrow helps recirculate the air in the car.

Lower The Temperature

Now that winter is here; you desire to stay in a warm environment. Unfortunately, the warm air in the car is the one causing the windows to get fog. So how do you deal with the warm air? Get ready to shiver, but know that the effort will be worth it. Turn down the temperature and turn on the fans to the highest settings. The temperature should be on the lowest levels you can withstand. Within a short time, the fog will disappear.                                                  

Turn The Defrost Vent on With Cold Air

Your main aim is to balance the air in the car with that on the outside. So when you turn on the defrost vent, the air goes to the windshield. The cold air will strike a balance between the air inside and that outside.

Imagine the frustration of fog build up on the windshield, and the wipers don’t seem to help. You might be tempted to get a rag, reach the windscreen on the outside and wipe while driving. That would be dangerous. If you must wipe, pull over, park your car, then wipe until you are satisfied. You may find that the windscreen has dirt and oil particles. They are stubborn to clean, and a simple cloth won’t help. Just take a soft cloth, put some soda or rubbing alcohol, and clean the windshield.

Foggy Windshield Fixes

One way of eliminating the fog faster is to use foggy windshield fixes. You can buy a bottle and keep it in the car and use it whenever necessary.

Open The Window

You can open the window at least an inch for the warm moist air to get out. Unfortunately, if it’s winter and it’s raining, opening the window isn’t a good idea. Once you get home, open the windows. The cold, dry air will get in. After a few seconds, close the window before going to the house. That will help to minimize fog formation.

How to Keep Car Windows From Fogging Up in The Rain

You can avoid the frustration of dealing with the fog when you are in a hurry. So, prevent the fog before it occurs. Here are a few ways

Deal With The Leaks

Remember, one of the fog’s causes is the excessive moisture from the water leaking in the car. Check if the door seals and the window weather stripping are working correctly. If they are not, have your mechanic take a look and replace them if need be. Ensure that the floor mat and the upholstery are dry since they can increase moisture if wet.

Clean The Window Shield

Dust on the surface of your windshield gives room for the condensation to cling on. So, clean the windshield using windshield cleaner and lint-free cloths. You can also use anti-fog products to help you prevent it from building up on your windshield. Shaving cream can also act as a defogger. Just smear it on the windshield then wipe it out.

Deal With Wet Items

If it’s raining, it’s hard to shake off all the water from your coat or umbrella. Ensure that before getting in the car, shake off the excess water from your boots, umbrella, and coats, and any other item that got wet.

Remember, if you leave drinks open overnight in the car, the moisture level will increase. So before leaving the car, ensure their seal is intact.

Moist Absorbent Item

A fresh kitty little can act as a basic dehumidifier. Put on some socks and put them in your car to help pull moisture off the air. You can also put absorbent silica gel in your car to sack excessive moisture off the air.

Use Potatoes

Take a clean raw potato and cut it into two. Rub your window using one-half. The main aim is to form a protective layer that ensures that condensation doesn’t form on your windows. Wipe off any starch streaks immediately before they stick on the window. You can use one or both halves. Once you are through, let the car dry and don’t touch it. Dispose of the halves safely.


It’s important to know what’s causing fog in your car. You will deal with the fog and prevent it from reoccurring in the future. For instance, you can check the reason why leakage is occurring and have it repaired. You can use the right products to keep the fog from accumulating on your windshield. Other things you might ignore as dust particles do attract fogs. Knowing how to deal with fog is a prerequisite for every driver. It’s therefore imperative to know that it is caused by the temperature difference between the air inside and that outside the car. Most modern cars have air conditioners that help you keep fog at bay.

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