Mount Waiʻaleʻale /ˌwˌɑːlˈɑːl/ is a shield volcano and the second highest point on the island of Kauaʻi in the Hawaiian Islands. Its name literally means "rippling water" or "overflowing water".[1]

Waiʻaleʻale (or 'Rippling Waters') Lake, the namesake of Mount Waiʻaleʻale.
Highest point
Elevation5,148 ft (1,569 m)
Prominence1,569 m (5,148 ft) Edit this on Wikidata
Coordinates22°04′26″N 159°29′55″W / 22.07389°N 159.49861°W / 22.07389; -159.49861
Waiʻaleʻale is located in Hawaii

The mountain, at an elevation of 5,148 feet (1,569 m), averages more than 373 inches (9,500 mm) of rain a year since 1912, with a record 683 inches (17,300 mm) in 1982; its summit is one of the rainiest spots on earth.[2] However, recent reports mention that over the period 1978–2007 the wettest spot in Hawaii is Big Bog on Maui (404 inches or 10,300 mm per year).[3]



Climate and rainfall statistics

Waterfalls around the caldera
The "Wall of Tears" in the crater of Mount Waialeale

The summit of Waiʻaleʻale features a tropical rainforest climate (Köppen Af), with substantial rainfall throughout the course of the year. (Bodin 1978: 272) quotes 460.0 inches (11,684 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.[4] The Weather Network and The Guinness Book of Weather Records (Holford 1977: 240) quotes 451.0 inches (11,455 mm) rain per year, while (Ahrens 2000: 528) quotes 460 inches (11,680 mm) as the average annual rainfall at Mount Waialeale and (Kroll 1995: 188) claims 510 inches (13,000 mm) falls here. Similarly, The Weather Network and the Guinness Book of Weather Records quote 335 days with rain here while (Simons 1996: 303) 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.

Climate data for Mount Waialeale
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Year
Average rainfall inches (mm) 24.78
Average rainy days (≥ 0.01 in) 20 17 20 26 27 27 29 29 27 27 21 21 289
Source: NOAA[5]


Sign at the park saying it is "one of the wettest spots on Earth"

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

  1. Its northern position relative to the main Hawaiian Islands provides more exposure to frontal systems that bring rain during the winter.
  2. Its peak lies just below the so-called trade wind inversion layer of 6,000 feet (1,800 m), above which trade-wind-produced clouds cannot rise.
  3. The summit plateau is flanked by steep walled valleys over 3,000 feet (910 m) deep on the three sides most consistently exposed to moisture bearing weather systems. These serve to funnel and concentrate any available precipitable water directly towards the mountain.
  4. The steep cliffs of the mountain's flanks generate intense orographic lift, causing the moisture-laden air to rise rapidly – over 4,000 feet (1,200 m) in less than 0.5 miles (0.80 km) – This combined with the 'barrier' of the trade-wind inversion, serves to very efficiently squeeze almost all of the moisture out of the incoming clouds directly over and immediately downwind of the peak.



The great rainfall in the area produces the Alakaʻi 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.[6]

See also



  1. ^ (Pukui, Elbert & Mookini 1974220).
  2. ^ "MT WAIALEALE 1047, HAWAII (516565)". WRCC. NOAA. 1 August 2008. Retrieved 30 August 2018.
  3. ^ "'Big Bog' ranks among wettest spots in Hawaii, possibly world - | News, Sports, Jobs, Visitor's Information - The Maui News". 2016-09-28. Archived from the original on 2016-09-28. Retrieved 2018-08-30.
  4. ^ "Global Measured Extremes of Temperature and Precipitation". National Climatic Data Center. August 9, 2004.
  5. ^ "Mount Waialeale – Climate Summary". National Oceanic and Atmospheric Administration. Retrieved August 21, 2010.
  6. ^ USFWS. Determination of endangered status for 48 species on Kauai and designation of critical habitat; Final rule. Federal Register April 13, 2010.


  • Ahrens, C.D. (2000), Meteorology Today, Brooks/Cole, ISBN 0-534-39776-X
  • Bodin, S. (1978), Weather and Climate, Blandford, ISBN 0-7137-0858-1
  • Holford, I. (1977), The Guinness Book of Weather Records, Book Club Associates
  • Kroll, E. (1995), De Wereld van het Weer, Teleac
  • Pukui, Mary Kawena; Elbert, Samuel H.; Mookini, Esther T. (1974). Place names of Hawaii (2nd ed.). University of Hawaii Press. ISBN 978-0-8248-0524-1. Place Names of Hawaii.
  • Simons, P. (1996), Weird Weather, Little Brown and Company