Immediately after getting certified many years ago, I took the AOW course in Cozumel. Back then, a night dive was required. We did it from shore, diving an airplane wreck. It had been a beautiful day, and we geared up as the sun was setting. It was just starting to get dark when we entered the water and headed out toward the wreck. We had a great dive, and when we got back to shore and surfaced. we were greeted by a beautiful starlit night. I took my gear apart and headed out across the parking lot by what was then the only cruise ship pier to catch a taxi. The parking lot was FULL of water. WTF? I got to the road, and there was water everywhere. When I got into the taxi, I asked if it had rained. Oh, yes, it certainly had. There had been one hellacious thunderstorm, with torrents of rain. Back at the hotel, my wife confirmed it all.
Years later, back in Cozumel again, we surfaced from a great dive to see the boat crew dressed out for foul weather, but it was a sunny day. We learned that while we were enjoying our dive, there had been a storm so bad that it had sunk 5 boats. My wife had been in a restaurant, and she had to climb on a table to escape flooding.