 The area 's rainfall averages 134 centimetres ( 53 in ) annually , varying from 50 centimetres ( 20 in ) at its lowest to 225 centimetres ( 89 in ) at its highest . Precipitation between May and August ( primarily snow ) is normally 20 to 35 centimetres , dropping to below one centimetre during summer . Temperature is also variable , typically registering 25 degrees Celsius during the summer , but dropping below freezing at high elevations ( above 2 @,@ 500 metres ( 8 @,@ 200 ft ) ) . 
