How rare is it for a hurricane to hit Hawaii?
How rare is it for a hurricane to hit Hawaii? Extremely rare.
Hurricanes roam the central Pacific, but actually hitting one of Hawaii’s main islands is unusual. The last hurricane to make landfall anywhere in Hawaii was Iniki on Kauai in 1992, and no hurricane has made landfall on the Big Island in the modern weather record.
That’s why Tropical Storm Lala has the attention of weather nerds this weekend.
As of Saturday morning, Lala was already bringing rain and tropical storm-force winds to portions of Hawaii while approaching the Big Island.
And what happens next could become part of Hawaii’s weather history.
What is Lala expected to do Saturday?
As of 8 a.m. HST Saturday, Lala had strengthened to 70 mph, putting it just 4 mph below hurricane strength. Its center was near 18.9°N, 155.0°W, moving west at 12 mph.
The latest forecast calls for Lala to become a hurricane as it passes very near the southern Big Island.
The forecast track brings the center extremely close to the island, potentially over or just south of it. But the center line is not a guaranteed track, so we still shouldn’t say Lala will make landfall as a hurricane.
The exact track, and when or whether Lala reaches the 74 mph hurricane threshold, will determine what eventually goes into the history books.
That does not mean a hurricane landfall is guaranteed.
The exact track and exactly when or whether Lala reaches the 74 mph hurricane threshold will determine what eventually goes into the history books.
A Hurricane Warning was in effect for the Big Island Saturday morning, while Tropical Storm Warnings covered Maui County, Oahu and Kauai County.
But why is the possibility of a hurricane hitting Hawaii such a big deal?
How rare is it for a hurricane to hit Hawaii?
Very rare, especially compared with hurricane-prone parts of the mainland United States.
Hawaii may sit in the middle of the Pacific, but the islands themselves are tiny targets in an enormous ocean.
NOAA’s historical hurricane-track database shows only a handful of hurricanes passing within a few hundred miles of the islands. NOAA notes that the Big Island has never been struck by a hurricane since modern weather records began.
The last hurricane landfall anywhere in the state came 34 years ago.
Hurricane Iniki slammed into Kauai in September 1992. The National Weather Service described Iniki as by far the strongest and most destructive of the hurricanes that had affected Hawaii since 1950.
But here’s where this story gets really nerdy.
Because saying a hurricane has never hit the Big Island isn’t quite right.
Wait. A hurricane may have hit the Big Island before?
Apparently, yes.
You just have to travel back 155 years.
University of Hawaii atmospheric scientist Steven Businger researched historical newspaper accounts and found evidence that a powerful hurricane struck the northeast corner of the Big Island in 1871.
The historical evidence indicates it may have been equivalent to a Category 3 hurricane.
There were no weather satellites watching the Pacific. No Hurricane Hunters flying through the storm. No modern radar network or instruments measuring a neatly documented maximum sustained wind.
That’s why you’ll see two statements that initially sound contradictory:
No hurricane has hit the Big Island in the modern record.
And:
Evidence indicates a hurricane did hit the Big Island in 1871.
Both can be true.
And if Lala were to make landfall at hurricane strength Saturday, AP reports it would be the island’s first direct hurricane landfall in 155 years and its first during the modern observational era.
So why doesn’t this happen more often?
Why do hurricanes so rarely hit Hawaii?
Part of the answer is simply geography.
Look at Hawaii on a map of the Pacific. Those islands occupy a remarkably small amount of real estate surrounded by thousands of miles of ocean.
A hurricane can pass 100 miles away and feel terrifyingly close while technically never making landfall.
But Hawaii also has some atmospheric protection.
Tropical cyclones approaching from the east can encounter less favorable ocean temperatures and atmospheric conditions. Steering patterns also frequently carry storms south of the main Hawaiian Islands.
The result is a strange relationship with hurricanes.
Hawaii can experience serious hurricane impacts without the hurricane itself ever actually hitting an island.
And that’s especially important with Lala.
Does Lala need to make landfall to be dangerous?
Absolutely not.
This may be the most important part of the entire story.
Lala’s outer rainbands were already reaching the Big Island Saturday morning. Forecast rainfall totals were 8 to 12 inches across Maui and lower elevations of the Big Island, with isolated amounts potentially reaching 25 inches in higher terrain on the Big Island.
That creates a potentially serious flooding and mudslide threat.
Hawaii’s mountains can make tropical rainfall particularly intense because moist air gets forced upward by the terrain. Wind can also accelerate dramatically over and around mountains.
In fact, forecasters warned that winds on some slopes and summits could be up to 30% stronger than the near-surface winds listed in the tropical cyclone advisory.
That’s why obsessing over whether Lala reaches exactly 74 mph can miss the larger point.
History cares about that number.
Floodwater doesn’t.
So could Lala make Hawaii hurricane history?
Yes.
But as of Saturday morning, that history had not happened yet.
Lala was still technically a tropical storm Saturday morning, but barely. At 70 mph, it was just shy of hurricane strength, and the official forecast called for it to become a hurricane near the southern Big Island.
Whether the center actually crosses the coastline, where it crosses and whether Lala has reached hurricane strength when it does will determine the historical answer.
But something remarkable is already happening.
A place that has not experienced a hurricane landfall in the modern observational record is under a Hurricane Warning, with a tropical cyclone strengthening on its doorstep.
And if you’re watching from thousands of miles away, that’s fascinating.
If you’re in Hawaii, forget the history lesson for a moment.
Pay attention to the rain, flooding, wind, surf and official warnings.
Because a storm doesn’t have to make history to make an impact.
Sometimes the most fascinating weather stories aren’t buried in an old book.
Sometimes you get to watch one unfold in real time.
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