Is it Bad to Wash Your Car in the Rain? Before or After?

We all deal with driving in the rain at some point. It can be tricky for keeping your car clean in the summer, but there are a few things you can do to work around it.

In this blog, I’ll break down everything you need to know about how the rain affects clean vehicles and give a few suggestions on when you should wash or detail your car with rain in the forecast.

Should You Wash Your Car in the Rain or Not?

In general, it’s not a good idea to actually wash your car in the rain if you are concerned with water spots.

This really has to do with several factors, one of them being the effects of acid rain in certain areas. Even in relatively small cities, rain still can still get contaminated by some level of smog or pollution.

Unless you plan on parking your vehicle until the road dries, it’s best to wait it out.

Don’t rely on rainstorms to clean your vehicle

Unfortunately, rain can only really help to wash away loose dirt or maybe pollen, but not stuck on bugs, tar, and other substances picked up from the road. While your car may look cleaner, once the rain dries things will likely look worse than they did before.

While it is true that rain can help knock some of the dirt off of your car, it’s not an excuse never to apply soap either by hand or via an automatic car wash.

Based on my experience, rainwater is pretty deceiving when it beads up, causing things to look a lot cleaner for a few hours until the water evaporates and contaminants are left behind on the paint.

Just keep this in mind before speeding through a puddle, since whatever salt, oil, dirt, or grease is on the road will soon be all over your car when everything dries.

The atmosphere and acid rain

As mentioned earlier, if you live in a large city like Los Angeles where acid rain is a problem, it’s even more important to wash this contaminated rainwater off as soon as you can.

Substances left behind by acid rain can etch into the clear coat of your car over time and make it harder to restore later on.

On the other hand, the effects of rain may not be as big of a deal in very rural areas with clean air. You may even notice fewer hard water spots since mineral-dense tap water will have been washed away by rainwater.

The reality is that while some people may prefer to wash their vehicles in the rain, it’s likely due to these hard water spots. Cleaner rain can only reduce water spots but is not a permanent solution.

Check out this blog post I wrote for everything you need to know about getting a spot-free wash.

Is It Better to Wash Your Car Before or After Rain?

It’s perfectly okay to wash a vehicle before it rains, just as long as you don’t plan on driving it around in the rain.

If you don’t own a garage, you may even want to go ahead and add a layer of wax or sealant, just to repel as much water as you can once the rain starts.

It’s ideal to wait until after if you can, you just want to make sure that you leave it parked long enough for the water to evaporate from the road.

Using a waterless product before the rain begins

I always like to keep a waterless spray handy in-between washes, and this can be helpful to add a small layer of protection against the rain. Be sure to use a waterless car wash product with plenty of lubrication if you plan on wiping away dirty rainwater.

Lubrication is the key to ‘sliding’ these dirty particles away, so do not just wipe the rainwater off with a towel. One product I like is Swift Wipe Waterless Wash by Chemical Guys.

If You Must, Find Shelter if it Starts Raining

If you do however get caught in a rainstorm in the middle of washing it’s probably okay for the most part as long as you have a place to dry your vehicle.

Letting your car air dry isn’t a great idea for most people, but as long as you have a garage to wipe your car down you should really have nothing to worry about.


For most people, it probably makes sense to just wait it out if you can. There are periods of time when rain is in the forecast nearly every day, in which case it’s perfectly okay for a quick wash. You may even want to think about a canopy if you live in an area that experiences a lot of rainfall.

Protecting your Vehicle

Even if you have to drive in rain every day, a properly protected vehicle will look a lot better once the rain dries than an unprotected one.

The real purpose of wax is to protect (not shine), so as long as you keep a good layer of wax or sealant on your vehicle, you should be able to limit the damage caused by dirty rainwater.

Just try to avoid those puddles :)

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