When travelling, we recommend packing in preparation to handle common weather conditions. The rainfall in St John is typically greater than that of Nice. We can gather that this will continue over the next 18 days.
Expect the weather to be around 28 °C on average in July. As the temperature peaks, try to get your plans done early, as flight price and availability will have an impact on your travels. The climate in Nice is generally hotter than in St John.