Weather is probably a major factor when you plan your trip to San Borja, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually September and October, with an average temperature of 25°C, while the coldest months are July and June, with an average of 22°C. The rainiest months in San Borja are February, January, March and December, with each month seeing an average of 580 mm of rainfall.