Planning for the weather is an important factor for making your trip to Rio Hondo a success, especially when you're splurging. The hottest months are usually April and May, with an average temperature of 25°C, while the coldest months are January and December, with an average of 22°C. The rainiest months in Rio Hondo are June, September, July and August, with each month seeing an average of 282 mm of rainfall.