When travelling, it's generally smart to pack in preparation for rain or any other conditions that may arise. The rainfall in Knock is roughly greater than that of Naples. You can assume this to be the case over the next 23 days.
You can imagine temperatures to be in the 31 °C range in July. The weather in Naples is generally hotter than Knock's. As flight availability is subject to become more limited as peak season approaches it is ideal to book in a timely manner.