 This area, like much of the West Coast region, is subject to high precipitation by world standards.There are no rainfall gauges on Mount Adams, but a gauge in Whataroa valley at the State Highway 6 bridge 10 km south-west of the summit at 60 metres above sea level, records a mean annual rainfall of 5690 mm (224 inches) and daily falls of up to 320 mm (12 inches).It is likely that the precipitation at higher elevations on Mount Adams will be significantly greater than this, and a rain gauge in the Cropp River 42 km north-east of Mount Adams at 860 metres above sea level, records a mean annual rainfall of 10,690 mm (421 inches) and daily falls of up to 695 mm (27 inches).