If you’re looking forward to lots of outings with your partner, take a look at these details about year-round temperatures in Cañas: The hottest months are usually March and April, with an average temperature of 27°C, while the coldest months are December and January, with an average of 25°C. The rainiest months in Cañas are October, September, June and August, with each month seeing an average of 498 mm of rainfall.