Question on common meme/belief

[seawasp]

It's a common meme in TV shows and commercials that a man will just finish washing his car and then it rains. The expression and setting usually doesn't indicate that he's thinking "Darn, if I'd just waited twenty minutes..." but rather "damn, this wipes out all my work!".

Why would this be so? (Note, I have washed a car I think precisely once in my entire life, so I have no experience to apply here)

Comments

[janetmiles.livejournal.com]

Because the rain will leave spots and streaks on his car, which he has gone to great lengths to make shiny and pristine.

[kgbooklog.livejournal.com]

Rain water isn't clean, especially if it's a light rain after a drought. Plus your next car trip will likely involve driving through dirty puddles. That said, I'm all in favor of letting mother nature do most of the work.

[amberdine.livejournal.com]

Yep.

Also, midwestern summer weather patterns are such that particularly warm and sunny weather often means approaching thunderstorm.

[janetmiles.livejournal.com]

That's very true -- I remember in Phoenix that rain was almost always preceded by a dust storm, so the first several minutes of rain were more like mud. And if there were only a few minutes of rain, well . . . .

[beamjockey.livejournal.com]

Why will the rain leave spots and streaks on the car? It's fairly pure water, with a negligible concentration of dissolved minerals, isn't it?

[kengr]

You wish.

Rain is often accompanied by wind (before, after or during. And that *will* find dust to pick up.

[cateagle.livejournal.com]

Well, around here it's either the rain washing dust out of the air onto whatever it lands on, and leaving it there, or the clouds picking up dust that gets mixed with the rain because my windshield is, more often than not, rather covered in dust after a rainstorm and you can see the final shape of the drops as they dried on there.

[fengi.livejournal.com]

I suspect it's partially the waxing part, which rain is more likely to ruin, but overall the meme originated back when a car's paint job actually needed washing and waxing to look decent and last. Now a car can appear clean just by being left in the rain, though the few times I've either done or purchased a hand wash rather than just running it through the machine the results are better.

[ninjarat.livejournal.com]

Aside from minerals there is a fair concentration of dust, pollen, and whatever other crap is in the air between the clouds and the ground. Never mind all the oil and grime that gets flushed out of the asphalt by the rain which is then sprayed all over everything on the road by the tires.

Why, yes, I did have my car washed this morning. Why, yes, we did have a spate of thundershowers this afternoon. :P

[stevegreen.livejournal.com]

Indeed. I live seven miles from a major airport and even though I'm not on the actual flightpath, there is frequently fuel residue in the rainwater.

[purplekitte.livejournal.com]

I've never washed a car when not doing it for the sole purpose of performing a modern-day rain dance. It's always coincidentally worked for me, though once the result was a hilarious five minute shower over maybe four square blocks.

[rdmasters.livejournal.com]

To do this properly requires a critical mass of any/all of the following:
* People washing cars for the express purpose of getting them clean
* People walking without umbrellas
* Clean, dry washing on clothes-lines
* Holes in the roof

This must be balanced against any people:
* Planting
* Ploughing
* Carrying umbrellas
And any low levels in the local catchment areas.

There is also the problem of excessive summoning, which can scare the rain off (i.e. don't try too hard), so the problem of calculating the exact range and mix of variables is a topic of hot research.

[xander-opal.livejournal.com]

Actually, planting/fieldwork is on the summoning side, as one does not want mud gumming up the machinery.