Planning for the weather is a good way to make your trip to Isla Grande relaxing and enjoyable, especially when you're splurging. The hottest months are usually May and September, with an average temperature of 27°C, while the coldest months are January and February, with an average of 26°C. The rainiest months in Isla Grande are November, July, August and October, with each month seeing an average of 350 mm of rainfall.