- It is rare for hurricanes to reach Hawaii, but tropical systems often make landfall.
- In El Niño years, activity in the Central Pacific is typically higher.
- The most dangerous hurricanes come from the south.
Hawaii may be a paradise, but just like in the Caribbean, hurricanes are part of its history.
The central Pacific basin – between 140 and 180 degrees west longitude – sees an average of four to five tropical cyclones per year, according to Dr. Rick Knabb, hurricane expert at The Weather Channel and former director of the National Hurricane Center. About two-thirds of these systems move westward from the eastern Pacific basin.
From 1950 to 2021, about 30 hurricanes passed within 200 nautical miles of the Big Island, Maui, Honolulu or Kauai, according to NOAA’s historical hurricane database.
The last hurricane to do this was Category 4 Hurricane Douglas in July 2020, which was centered just 30 miles north of Oahu. Douglas’s wind gusts knocked down some trees and created rainbands in parts of the islands, causing localized flooding.
As Eric Webb, a doctoral student at the University of North Carolina-Charlotte, pointed out, a major hurricane struck the Big Island and Maui in August 1871, a study found in January 2018.
The fact that this does not happen very often is partly due to geography.
The total land area of Hawaii in the vast Pacific Ocean is only about 6,400 square miles. This makes Hawaii the fourth smallest U.S. state in terms of area and only larger than Connecticut, Delaware and Rhode Island.
August is the month with the highest number of tropical cyclones in the Central Pacific Basin. According to the Central Pacific Hurricane Center, between 1971 and 2013 there were twice as many (74) as in September (37). Unlike in the Atlantic Basin, July is the second most active month in the Central Pacific Basin (45).
Dr. Knabb, former deputy director of NOAA’s Central Pacific Hurricane Center in Honolulu, points out that there is no meteorological reason why the core of a major hurricane could not strike Honolulu directly, causing devastating storm surges, storm damage and rain flooding that would affect a city population of nearly 400,000 (not including tourists).
How Hawaii is hit by hurricanes
Hawaii has been and will continue to be hit by hurricanes. The key, at least from a climatological perspective, is the direction the storm is coming from.
Most tropical cyclones that reach the 50th state come from the east or south, but occasionally from the southwest.
In most years, the water is too cool for most tropical systems to come from the east. This is because water currents bring cooler water from Alaska across the eastern Pacific along the U.S. West Coast into the central Pacific.
Factors that weaken tropical cyclones in Hawaii
Sea surface temperatures typically rise the further south you go in the North Pacific, meaning a tropical cyclone moving toward Hawaii from the south would have a better chance of surviving to the islands.
Any south or southwest winds aloft would direct a hurricane toward the island chain. Even a hurricane simply circling the southwest side of a less extensive subtropical high in the eastern Pacific would put Hawaii in the crosshairs.
In El Niño years, this idea changes somewhat.
El Niño allows warmer water to move further north into the typical east-west movement of tropical systems from the eastern Pacific. The warmer water also allows more tropical systems to form closer to Hawaii and across the eastern Pacific.
Hurricane expert Michael Lowry states that since 1950, the probability that a named storm will pass within 100 miles of the Hawaiian Islands in an El Niño year is 13 percent greater (35 percent probability) than in a neutral year (22 percent probability).
Another side effect of El Niño is that the trade winds that sometimes trap tropical cyclones far south of the islands weaken, making it easier for these persistent storms south of the islands to be pulled north. Of course, an El Niño is no guarantee that a hurricane will hit Hawaii.
A sidewalk is torn up and littered with fallen palm trees after Hurricane Iniki devastated the island of Kauai, Hawaii in September 1992.
(NOAA)
One of these hurricanes occurred in an El Niño year: 1992.
The most destructive hurricane in Hawaii’s history, Hurricane Iniki originated as Tropical Depression Eighteen-E in the eastern Pacific on September 5, 1992. The depression then moved into the central Pacific basin west of 140 degrees longitude, where it developed into a tropical storm and eventually a major hurricane. This track also initially passed well south of Hawaii before drifting northward.
The island of Kauai was particularly hard hit by destructive winds. On the south coast, many buildings were destroyed by storm surges and large, stormy waves.
Climate change, with rising water temperatures, could lead to more frequent storms that make their way from the eastern Pacific to Hawaii.
Don’t fear the East most of the time
Virtually every system that has approached Hawaii from the east since 1950 and reached at least as far north as the Big Island of Hawaii eventually weakened to a tropical storm or depression before reaching the islands.
This includes several Category 4 hurricanes in the eastern Pacific that fizzled out, such as Felicia (2009), Orlene (1992) and Raymond (1983).
There are several reasons why this happens so often.
- Drier, more stable air from the subtropical highlands in northeast Hawaii ultimately prevents thunderstorms from forming permanently and remaining concentrated near the cyclone center.
- Wind shear (the change in wind speed and/or direction with altitude) is typically stronger near the Hawaiian Islands and causes thunderstorms to be displaced from the center of the cyclone.
- The cooler temperatures at the ocean surface in the Pacific east of Hawaii’s Big Island ensure that the air above it stays slightly cooler. This makes the atmosphere more stable and less prone to the formation and maintenance of thunderstorms.
Of course, this does not mean that this will be the case for every single storm in the future. This is the reality of a meteorological rule of thumb.
There has not been a report of a hurricane making landfall on the Big Island of Hawaii since 1950. Tropical Storm Iselle in 2014 was only the second tropical storm to make landfall on the Big Island since 1950, and the strongest. The only other storm to do so was in 1958.
Other current hurricanes and tropical storms in Hawaii
- Lane, 2018: A Category 5 hurricane that rapidly weakened as it approached Hawaii but still caused flooding on the Big Island, where rainfall amounts of over 50 inches made the storm one of the most severe tropical cyclones in U.S. history.
- Hector, 2018: Weakened from a Category 4 hurricane in the eastern Pacific to a tropical storm as it approached Hawaii. Several dozen people on Oahu were rescued from high surf.
- Lester, 2016: A Category 4 hurricane in the eastern Pacific weakened as it approached Hawaii. The storm passed well north of the islands as a hurricane. Minor flooding was reported on some islands.
- Darby, 2016: Darby weakened as it approached the island of Hawaii, but brought heavy rains and flash flooding to much of the Big Island. This was the second tropical storm to make landfall on the Big Island in less than two years.
- Iselle, 2014: Made landfall as a moderate tropical storm in the far east of Hawaii. More than 10 inches of rain fell in many locations on the east side of the Big Island, causing moderate flooding. The first of two landfall storms in two years on the east coast of the Big Island. Only one of seven deadly tropical systems to hit Hawaii. The system caused over $150 million in damage.
