Weather is probably a major factor when you plan your trip to Pamplona, but bear in mind that cheaper options are usually available when the weather isn't as good. The hottest months are usually September and January, with an average temperature of 14°C, while the coldest months are January and December, with an average of 14°C. The rainiest months in Pamplona are May, April, October and November, with each month seeing an average of 281 mm of rainfall.