Mount Waialeale is a shield volcano and the second highest point on the island of Kauai in the Hawaiian Islands. Its name literally means crippling water" or "overflowing water". The mountain, at an elevation of 5148 ft, averages more than 373 in of rain a year since 1912, with a record 683 in in 1982; its summit is one of the rainiest spots on earth. However, recent reports mention that over the period 1978–2007 the wettest spot in Hawaii is Big Bog on Maui (404 in per year).

Climate

Climate and rainfall statistics

The summit of Waialeale features a tropical rainforest climate (Köppen Af), with substantial rainfall throughout the course of the year. quotes 11684 mm per year figure as being the 1912–45 average, an average that quite possibly will have changed since then, while The National Climatic Data Center quotes this figure as a 30-year average. The Weather Network and The Guinness Book of Weather Records quotes 11455 mm rain per year, while quotes 11680 mm as the average annual rainfall at Mount Waialeale and claims 13,000 mm falls here. Similarly, The Weather Network and the Guinness Book of Weather Records quote 335 days with rain here while suggests that rain falls on 360 days per year. The local tourist industry of Kauai has promoted it as one of the wettest places on earth, which it is. The rainfall at Waiʻaleʻale is evenly distributed through the year.

Causes

Several factors give the summit of Waialeale more potential to create precipitation than the rest of the island chain:

Ecology

The great rainfall in the area produces the Alakai Wilderness Preserve, a large boggy area that is home to many rare plants. The ground is so wet that although trails exist, access by foot to the Waiʻaleʻale area is extremely difficult. A number of rare local plant species are named for this mountain, including Astelia waialealae, Melicope waialealae, and the endemic Dubautia waialealae.

Sources