My point is fresh water is a poor conductor of electricity but it's conductivity can be greatly increased by adding salt or sometimes other elements that will dissolve. For instance when I left the cap off my 12v outlet on the bike and parked it, a late night rain storm filled the live socket with water. It did not short anything or drain the battery even though the bike sat for over 12 hours with a live 12V socket full of water. On the other hand rain water will sometimes cause a high voltage line to arc over a cracked insulator where it will not do so in the dry. I had a summer job with the local electrical utility once, inspecting high voltage lines. It conducts slightly better than air but not anywhere like a true conductor. The movies where someone is murdered by throwing a toaster in the bathtub is based on false science.
"Pure water is not a good conductor of electricity. Ordinary distilled water in equilibrium with carbon dioxide of the air has a conductivity of about 10 x 10-6 W-1*m-1 (20 dS/m). Because the electrical current is transported by the ions in solution, the conductivity increases as the concentration of ions increases." - Google
I spent over 30 years fixing inverters, and still consult, everything was water cooled. A fact of life using de-ion cartridges, ideal conductivity was 20 micro-siemens, which was roughly 1 million ohms with a 1/2 inch water line. The lower you go the more the water will try and re absorb from the copper coils, the tubing,above 40 micro siemens you get electrolysis. So having said that you would think, like yourself that there would be no issue with rain water getting into the 12 volt socket, so I too thought. This isn't a very good picture, but just to the right of the vacuum gauge is my distribution. I have a 12 volt outlet with a adapter plugged into it at all times for my GPS, this is under the plastic but I have been in some heavy rain / torrential downpours, last fall it would drop out and stop working.
What I found was the various metals started some corrosion / oxidation from rain water getting in, I have since formed a rubber cone above the outlet, end of problem. I was more or less trying to be funny siding with Eddie,
however, there is a huge difference between the amount of electric current it takes to kill a person and the amount of current it takes to produce a arc or cause carbon tracking. So wet skin conducts about 100 times better than dry skin https://www.quora.com/Safety-Why-doe...electric-shock
So I have done my due diligence, no one can say Onewizard said it was OK to touch the spark plug wire while the car was running and it was raining out, because it was rain water