In Nascar, why do they cover the cars when it starts to rain?

May be...

The paint jobs and numbers put on with are chalk and they don't want the chalk to wash off so they can tell the cars apart.

Lol. Ok I know the electronics are important too. But a big part is the driver really probable does not want the inside all wet ether. I mean do you all like a wet seat when you are driving your car.

To try to prevent any moisture entering the electronics. These cars do not have water proof electrical.

The moisture causes electrical shorts. The cars are not designed to run in the rain. They still have a tendency to get condensation in them when they cover them up while they are hot and it's cool outside because of the rain.

Most importantly so water doesn't get into electronics as well as the air intakes.

so the cars doun't get wet, duh

So the cars won't get wet.

To keep them dry.

Water will get under the hood if they don't.

race cars aren't built like the cars we drive on public roads. Race cars are high tech pieces of equipment that can be damaged by water getting into electrical components. Certain things aren't supposed to get wetnail-treatments