May and June are perfect out on the water for those who can’t do seriously hot, with temperatures around 23 -27°C, although the wind can be a bit unpredictable during these months.
The end of September marks the end of the season on some of the islands, with restaurants and bars closing for the winter. The great thing about traveling with local skippers, however, is that they know exactly which taverna is open and where. They know all the archipelago’s secrets.
However, many island vineyards are harvesting in October, which is a great time for local festivities. So this can be a wonderful time to visit islands like Vis or Krk.
If your small ship cruise takes place in April and over Easter, this is a wonderful time all over Croatia for processions and pilgrims, festivities and flowers.
In peak season, if you are doing city visits to Split or Dubrovnik, avoid the cruises that arrive into the big ports early in the morning, bringing a tidal wave of tourists. They all head back on board around 3pm generally, so time your city visit accordingly. There are ships all year round, but these are busiest times.
August really is peak of peaks in Croatia, and so if you are going to some of the popular spots on the coast, be prepared for crowds.
May is also gorgeous with temperatures around 23°C but the winds along the coasts are less predictable at this time, and storms can happen, so be prepared for flexible itineraries.
Many cruises begin and end in Dubrovnik, and so you could check out the Dubrovnik Summer Festival which runs through July and August. It is a world class event, a bit like Edinburgh International Festival in the sun, with arts performances from around the world, but with a strong backbone of Croatian culture.