Why does rain make your car dirty?
We are using the google “autocomplete” function to answer the most common questions you have about vehicle detailing.
It is a well known fact that if you wash your car in the morning there is a 99% chance that it will rain in the afternoon. That might not be entirely true, but it definitely feels like that sometimes. Why does it matter? Because we all know that rain makes your car dirty again. The real question is this: Why does rain make your car dirty in the first place? This is what we are here to answer.
When you have a science question, you need to find yourself a scientist. Atmospheric scientist Steve Ackerman explains this phenomenon by descibing the quality of the air in the lower atmosphere:
“The air near the ground has all kinds of particles floating in it: pollen, pollutants, dust, smoke, etc.” he says. “As rain falls out of a cloud and down to the ground, it sweeps out and collects these particles into the raindrop. So, after the rain wets your car and then dries up, it leaves behind these particles on your car.”
It seems that rain doesn’t just wash away spiders, it also washes the airborne dust out of the sky and deposits it on everything below, including your car. There may be an upside to this phenomenon, though. Have you ever noticed how fresh and clear the air is after an afternoon rain? That is the moment that the air quality is the best, even though it means another trip to local car wash.