Climate
[edit]
Main article: Climate of Hawaii
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The climate is characterized by a two-season year, tropical and uniform temperatures at any given elevation, geographic differences in rainfall, high relative humidity, extensive cloud formations (except on the leeward coasts and at the highest elevations), and dominant trade wind flow (especially at lower elevations).
Maui has a range of climatic conditions and weather patterns:
Half of the land is within 5 mi (8 km) of the coast, creating a strong marine influence.
Macro weather patterns are typically determined by elevation and orientation towards the trade winds (the prevailing air flow from the northeast).
Maui's rugged, irregular topography drives variations in conditions. Air swept inland on the trade winds is redirected by the mountains, valleys, and vast open slopes. This three-dimensional flow of air produces variations in wind speed, cloud formation, and rainfall.
Maui displays diverse climatic conditions, each of which is specific to a sub-region. These sub-regions are defined by major physiographic features (such as mountains and valleys) and by location on the windward or leeward side.
Maui's daytime temperatures average between 75 °F (24 °C) and 90 °F (32 °C) year round, while evening temperatures are about 15 °F (8.3 °C) cooler in the more humid windward areas, about 18 °F (10 °C) cooler in the drier leeward areas, and cooler still in higher elevations.
An exception to the normal pattern is the occasional winter Kona storm that brings rainfall to the South and West areas accompanied by high southwesterly winds (opposite of the prevailing trade wind direction).
Microclimates[edit]
West coast, with Haleakalā and Kihei visible in the background
Maui has examples of all microclimates, each typical to specific locations.
Makena Beach, South Maui
Windward lowlands – Below 2,000 ft (610 m) on north-to-northeast sides. Roughly perpendicular to the trade winds. Moderately rainy; frequent trade wind-induced showers. Skies are often cloudy to partly cloudy. Air temperatures are relatively more uniform (and mild).
Leeward lowlands – Daytime temperatures are higher and nighttime temperatures are lower than in windward locations. Dry weather is prevalent, except for sporadic showers that drift over the mountains to windward and during short-duration storms.
Interior lowlands – Intermediate conditions, often sharing characteristics of other lowland sub-regions. Occasional intense afternoon showers from clouds that form due to local daytime heating.
Leeward side high-altitude mountain slopes with high rainfall – Extensive cloud cover and rainfall all year long. Mild temperatures are prevalent, but humidity is higher than in any other sub-region.
Leeward side lower mountain slopes – Rainfall is higher than on leeward lowlands but much less than at similar altitudes on the windward side; however, maximum rainfall usually occurs leeward of the crests of lower mountains. Temperatures are higher than on the rainy slopes of the windward sides of mountains; cloud cover is almost as extensive.
High mountains – Above about 5,000 ft (1,500 m) on Haleakalā, rainfall decreases rapidly with elevation. Relative humidity may be ten percent or less. The state's lowest temperatures are experienced in this region: air temperatures below freezing are common.
These microclimates help to define the major regions: Central Maui; leeward South Maui and West Maui; windward North Shore and East Maui; and Upcountry.
Central Maui consists primarily of Kahului and Wailuku, and occupies the flat isthmus between the West Maui Mountains and Haleakalā. Kahului is the center of the island and tends to keep steady, high temperatures throughout the year. The Kahului microclimate can be muggy, but usually feels relatively dry and is often breezy. The Wailuku area is closer to the West Maui Mountain range. There, rainfall is greater throughout the year and humidity is higher.
South Maui (Kihei, Wailea, and Makena) and West Maui (Lahaina, Kaanapali, and Kapalua) are both on the leeward side. These areas are typically drier, with higher daytime temperatures (up to 92 °F (33 °C)), and the least amount of rainfall. (An exception is the high-altitude, unpopulated West Maui summit, which boasts up to 400 in (10,000 mm) of rainfall per year on its north and east side.)
Waianapanapa State Park in East Maui, next to Hana
The North Shore (Paia and Haiku) and East Maui (Keanae, Hana, and Kipahulu) are both on the windward side. Facing the prevailing, northeast trade winds, these areas have heavier rainfall levels, which increase considerably at higher elevations.
Upcountry Maui is the name for the sloping area on the western face of Haleakalā, including the towns of Makawao, Pukalani, and Kula. This area ranges from 1,500 ft (460 m) to 4,500 ft (1,400 m), and the climate tends toward mild heat (between 70 °F (21 °C) and 80 °F (27 °C)) during the day and cool evenings. The higher the elevation, the cooler the evenings: during Maui's winter, Upper Kula can be as cold as 40 °F (4 °C) in the early morning hours and the Haleakalā summit can dip below freezing and become covered in snow.
Climate data for Maui
Month
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Average sea temperature °F (°C)
76.3
(24.6)
75.5
(24.2)
75.3
(24.1)
75.9
(24.4)
76.8
(24.9)
77.7
(25.4)
78.6
(25.9)
79.3
(26.3)
80
(26.7)
80
(26.7)
78.9
(26.1)
77.1
(25.1)
Source: meteodb.com
Rainfall[edit]
Kahikinui coastline near Kaupo
Rainbow over the West Maui Mountains after rainfall in Kāʻanapali
Showers are common; while some of these are heavy, the majority are light and brief. Thunder and lightning are rare, even during intense storms. Throughout the lowlands, summer trade winds produce a drier season. Annual rainfall averages 17–20 inches (430–510 mm) in leeward coastal areas, such as the shoreline from Maalaea Bay to Kaupo. At the other extreme, the average exceeds 300 in (7,600 mm) along the lower windward slopes of Haleakalā, particularly along Hāna Highway. Big Bog, a spot on the edge of Haleakalā National Park overlooking Hana at about 5,400 ft (1,600 m) elevation had an estimated mean annual rainfall of 404 in (10,300 mm) over the 30-year period of 1978 to 2007. If the islands of Hawaii did not exist, the average annual rainfall on the same patch of water would be about 25 in (640 mm).[citation needed] Instead, the mountainous topography induces an average of about 70 in (1,800 mm).
Maui
Climate chart (explanation)
J
F
M
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J
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O
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33
 
 
20
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█ Average max. and min. temperatures in °C
█ Precipitation totals in mmSource:
Imperial conversion
JFMAMJJASOND
 
 
1.3
 
 
68
45
 
 
1.2
 
 
66
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1.6
 
 
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72
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79
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68
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0.5
 
 
68
43
█ Average max. and min. temperatures in °F
█ Precipitation totals in inches
In the lowlands, rainfall is most likely to occur during night or morning hours, and least likely in mid-afternoon. The most pronounced daily variations in rainfall occur during the summer because summer rainfall generally consists of night-time trade wind showers. Winter rainfall in the lowlands is the result of storm activity, which is as likely to occur in the daytime as at night. Rainfall variability is far greater during the winter when occasional storms contribute appreciably to rainfall totals. Such wide swings in rainfall produce occasional droughts, sometimes causing economic losses. These occur when winter rains fail to produce sufficient significant rain, impacting normally dry areas outside the trade winds that depend on them the most. The winter of 2011–2012 produced extreme drought on the leeward sides Maui, and some other islands.
Natural history[edit]
Maui is home to a large rainforest on the northeastern flanks of Haleakalā, which serves as the drainage basin for that side.
Maui is home to many coral reefs. However, many have been damaged by pollution, run-off, and tourism, although sea turtles, dolphins, and Hawaii's tropical fish remain abundant. Leeward Maui once had a dry cloud forest, but this was destroyed by human activities over the last three hundred years.
Wildlife[edit]
Main article: Endemism in the Hawaiian IslandsMaui is the leading whale-watching center in the Hawaiian Islands for the humpback whales who winter in Maui County's sheltered ʻAuʻau Channel. These mammals migrate approximately 3,500 mi (5,600 km) from Alaskan waters each autumn and spend November–April mating and birthing in the warm waters. They are typically sighted in pods: small groups of several adults, or groups of a mother, her calf, and a few suitors. Humpbacks are an endangered species protected by U.S. federal and Hawaiʻi state law. An estimated 21,000-26,000 humpbacks live in North Pacific waters. Although they face many dangers, due to pollution, commercial vessels, and military sonar testing, their numbers have increased rapidly in recent years, estimated at 7% growth per year. A green sea turtle near Maui
Turtle resting after a long swim in (Maui, Hawaii)
Birdlife lacks the concentration of endemic species found in some other Hawaiian islands. As recently as 200,000 years ago Maui was part of Maui Nui, thus reducing the odds that birds or other species would be endemic to any single one of these. Although Molokaʻi had several endemic bird species, in modern times Maui Nui's other islands host little endemic birdlife. During and after the Maui Nui period, Maui hosted a species of moa-nalo (also found on Molokaʻi, Lānaʻi, and Kahoʻolawe), a species of harrier (the wood harrier, shared with Molokaʻi), an undescribed sea eagle (Maui only), and three species of ground-dwelling flightless ibis (Apteribis sp.), plus other species. Today, Maui's most notable surviving endemic birds are probably the ʻAkohekohe (Palmeria dolei) and the Maui parrotbill (Pseudonestor xanthophrys), also known as Kiwikiu, both of which are critically endangered and only found in an alpine forest on the windward slopes of Haleakalā.
Conservation efforts have examined how to mitigate female parrotbill mortality since that is a key driving factor driving population decline. The parrotbill lacks resistance to mosquito-born diseases, particularly avian malaria, so only forests above 1500 meters of elevation provide refuge. The habitat was undergoing restoration in east Maui as of 2018. As Maui's human population grew, previously undeveloped areas that provided a refuge decreased in size. More than 250 species of local flora are federally listed as endangered or threatened. Birds found on other islands as well as Maui include the ʻIʻiwi (Drepanis coccinea], ʻApapane (Himatione sanguinea), Hawaiʻi ʻAmakihi (Chlorodrepanis virens), as Maui ʻAlauahio (Paroreomyza montana) well as the Nene (Branta sandvicensis, Hawaii's state bird), Hawaiian coot (Fulica alai), Hawaiian stilt (Himantopus mexicanus knudseni).
In 2024, Haleakalā National Park began to employ the incompatible insect technique to reduce the park's mosquito population.
Maui is also home to the Hawaiian hoary bat, Hawaii's only native terrestrial mammal. Marine mammals notably include spinner, bottlenose, and spotted dolphins.
