Weather will likely play an important role when you plan your trip to San Fernando, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually September and May, 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 San Fernando are August, July, November and October, with each month seeing an average of 178 mm of rainfall.