I have been asked numerous amounts of times about safety and jump-starting the car in the pouring rain and my answer has always been “Yes, it is completely safe to jump-start a car in rain.”
Hang on, I’ll explain this.
Most of the car’s electrical system runs on DC 12 volts (or 24 volts if it is a big truck) and 5v. And the amperage of the car battery is around 48 to 50 Ah. This voltage and current range are very safe to work with and there is not a chance that you can hurt yourself while jump-starting a car in the rain.
Some people might not know how often car’s under-hood gets splashed with water when driving during rain and on wet roads. And that does not cause anything to go bad or batteries to shoot sparks.
So the car’s electrical system is designed to stay safe in wet conditions.
And when it comes to using a portable jump starter, to jump-start a car in rain, it is also very safe. As safe as jump-starting a car on a sunny day.
Most of the good quality jump starters have their 12V jumper ports covered with plastic or rubber protection caps to keep the water and the moisture out.
So instead of worrying about rain during a “jump-start” situation, you should be worrying more about hooking the terminals the wrong way (if your jump starter does not have reverse polarity protection).
And if you are jump-starting with another car, then you should be extra careful about polarity and always double-check the connections.
So the only things you should worry about jump-starting a car in the rain are not slipping on wet ground, and not catching a cold. Everything else is safe.
On the other hand, the only electrical system in the car that can hurt you is the car’s ignition system.
It produces a lot of voltages but a very small amount of amps. And the shock from such voltages feels like a stun gun. Not enough to kill you but more than enough to make you remember to not touch that thing again.
And don’t ask in the comments on how I know about this.