How much precipitation is on the slopes of the Northern Andes?

The slopes of the Northern Andes receive about 200-500 mm of precipitation per year.
The northern Andes belongs to the subequatorial belt of the Northern Hemisphere; therefore, as in the subequatorial belt of the Southern Hemisphere, there is an alternation of wet and dry seasons; precipitation occurs from May to November, but in the northernmost regions the wet season is not so long. The eastern slopes are more humid than the western ones; precipitation (up to 1000 mm per year) falls mainly in summer.