A member of our club has spent the summer months in Croatia. Whilst he loved the scenery he is planning to go elsewhere next year because of the sudden storms.
During the course of the season he got caught in about 12 of them.
I would love to explore Croatia but SWMBO would probably vow never to set foot on a yacht again if we ended up in a storm out there.
I have met it two times. All around were calm and something happening that in hundred square meters start swirl. Competent people from weather institute don’t know the reason. One thing is sure - always was coming from great Cumulo nimbus.
Saw 2 small water spouts on the Shannon estuary in 2004. They formed before our eyes but didn't ground. It was the remains of hurricane Alex which parked 100m off the SW coast for 2 weeks.
Regarding SWMBO ! This thing can happen everywhere, but generally sailing in Croatia is painless for SWMBOs.
Once upon a time first lesson for my wife was: "When you step on the boat you can get and bad weather too!" and after decades of sailing she still sail!
I have seen it by myself. Was anchored in Milna and saw two of them not so far in the chanel between Brac and Solta.
And 4 days later, got a "nevera" : from 0, flat sea, to 45 knots of wind in less than 1,5 minute ! Motor full ahead i just succeeded to stay wind in the nose at 0,5 knots....