When travelling, it's generally smart to pack in preparation for rain or any other conditions that may arise. The rainfall in Cork is roughly greater than that of Dubrovnik. You can assume this to be the case over the next 27 days.
Our data indicates that the weather will be 29 °C on average in the month of July. The temperature in Dubrovnik is typically hotter than in Cork. If you're traveling when the temperature is at its warmest, push to plan early, as flight price and availability will have an impact on your travels. For the best results, search for flights well in advance or after peak season.