When something like that happens, it's best to give it time to dry out before powering it back up, esp. if it was OFF at the time (I know, not likely). However, ppl’s natural inclination is to immediately power it back up to see if it’s alright. And that can be your undoing.
At this point, I would find a dry, warm location, perhaps even outside, and let it dry out for several days and try again. Resist the temptation to retry too quickly.