Lala recently claimed the interesting title of being the longest-lived tropical cyclone ever to exist entirely within the Central Pacific. This distinction is mostly an artifact of how tropical cyclones are classified: the enormous breadth of the Pacific north of the equator is divded into three areas, according to the meteorological center responsible for issuing advisories on tropical cyclones in the area.
The East Pacific extends from the coastline of the Americas to 140°W, and is administered, along with the north Atlantic, by the National Hurricane Center in Miami, Florida. Cyclones in this region are called hurricanes. The West Pacific is defined to extend from 180 (the International Dateline) to Asia, specifically the 100°E line of longitude, and is administered by the Typhoon Center in Tokyo, Japan. Cyclones in this region are called typhoons. In the middle, between 140° W and the Dateline, is the Central Pacific, administered by the Central Pacific Hurricane Center in Honolulu, Hawaii.
The images above show the headquarters of the Central Pacific Hurricane Center (CPHC), established 1970. It is located on the campus of the University of Hawaii at Manoa. I actually took these photos myself on a recent visit to the campus.
As mentioned, these boundaries are not meteorologically significant. In fact, tropical cyclones frequently cross between these regions. This creates some fun naming quirks. The terminology of "tropical storms" and "hurricanes" are used the same way in the Central Pacific as in the Eastern Pacific and Atlantic. However, a "Hurricane X" crossing the International Dateline westward changes to "Typhoon X", preserving its name but changing its title. In the tropics, most tropical cyclones move westward, so it is quite common for cyclones to cross from the Eastern to Central Pacific, and not unusual for Central Pacific cyclones in turn to cross to the West Pacific. Farther from the equator, tropical cyclones often "recurve" toward the northeast due to the midlatitude westerly winds, so occasionally a crossing happens in the other direction. A notable example is Hurricane/Typhoon John of 1994, whose track is shown below.
John formed and was named in the Eastern Pacific, crossed to the Central, passed south of Hawaii, crossed the International Dateline and was renamed "Typhoon John", and finally crossed back into the Central Pacific near the end of its long journey. John still has the longest total track of any tropical cyclone on record. Many years ago, a previous post on this blog discussed John's track in some detail, though its longevity record has since been usurped by Cyclone Freddy of the southern Indian Ocean.
Since John made three of the four possible crossings, it's natural to ask whether a cyclone has ever done the remaining one: crossing from the Central Pacific eastward into the Eastern Pacific. This is far rarer because the mid-latitude east Pacific waters are comparatively cold, and tropical cyclones usually fizzle before recurving. One notable historical example is Hurricane Ulika of 2016.
The tropical depression that became Ulika formed in the eastern Pacific in September 2016, just east of 140°W, crossed into the Central Pacific, was named there, crossed back into the Eastern Pacific, and then crossed again into the Central before losing tropical cyclone status.
Each region also uses its own naming system, and a cyclone always keeps its name from the first time it achieves tropical storm strength ("John" came from the Eastern Pacific, "Ulika" from the Central). The Atlantic and Eastern Pacific use familiar alphabetical lists of storms that begin at "A" each year, rotating in a six-year cycle. In contrast, the Central Pacific uses four lists of twleve names each, which do not reset each year but rather pick up where the last year left off. The name "Lala" was the first used in the Central Pacific in 2026, picking up from "Keli" in 2025. Just as in the other regions, the names of particularly damaging cyclones are retired. The full lists can be found here; they use traditional Hawaiian names and were selected in partnership with cultural experts. The name "Lala" means "branch" or "tree limb" in Hawaiian.
One reason for the difference in naming convention is that relatively few cyclones are named in the Central Pacific, compared to its eastern and western neighbors.
The image above shows the total number of named storms in the central Pacific for each year from 1970-2013 including storms that formed in other regions and crossed over. These numbers are already smaller than neighboring basins, and the number of names used from the Central Pacific lists per year is far smaller. This is mainly due to the low atmospheric humidity in the region and a persistent upper-level troughs of low pressure that tend to shear apart nascent storms.
The El Niño Southern Oscillation (ENSO) cycle, however, has an outsized effect on Central Pacific activity. This multi-year cycle is a trend in the temperature anomalies in the equitorial Pacific ocean; positive anomalies lead to an "El Niño" and negative ones to a "La Niña". Studies show that Central Pacific activity doubles during El Niño, compared to La Niña. This brings us at last back to 2026, as this summer has seen possibly the largest El Niño in recorded history take shape.
On August 9, 2026, a tropical wave entered the Central Pacific, moving west-northwestward. The disturbance was large but organized steadily, taking advantage of higher than normal oceanic heat content and favorable atmospheric conditions. Early in the morning on August 13, Hawaii time, it was named Tropical Storm Lala, around 700 miles (1100 km) east-southeast of the Big Island. Not all factors were in favor of intensification: Lala had some mid-level dry air to contend with, and was somewhat asymmetric, with most convection and winds north of the circulation center. Nevertheless, the storm gradually deepened, and was a strong tropical storm by late on the 14th. Early the next morning, its outer rainbands swept across the Big Island, with tropical storm force winds beginning shortly thereafter. Lala strengthened some more during its final approach to the Big Island, and peaked as a category 1 hurricane with maximum sustained winds of 80 mph (130 km/hr) and a central pressure of 985 mb as the center passed within 30 miles (50 km) of the southernmost point of Hawaii around 5pm local time.
The image above shows Lala at its first peak as it passed close to the Big Island. As discussed further below, the size of the storm meant that significant storm impacts were felt across the Hawaiian islands, even though the hurricane did not technically make landfall. After its close passage, dry air flowing off the mountains of Hawaii temporarily weakened the storm, bringing it down to tropical storm status. Lala turned westward away from the island chain, and most impacts even to the westernmost main Hawaiian islands had ended by late on August 16.
Lala had limited atmospheric moisture to work with and was battling some shear, but the increasingly warm waters it traversed were enough to begin another strengthening trend the next day. The storm put on an impressive display and made it all the way to category 4 intensity late on August 18. The peak intensity was 130 mph (210 km/hr) winds with a central pressure of 947 mb. The image at the beginning of this post shows Lala around that peak.
Meanwhile, the storm was turning toward the right as the ridge north of it weakened. The rest of Lala's history was mostly a slow weakening trend. It passed over the uninhabited northwestern Hawaiian islands and atolls still as a category 1 hurricane on August 20. After a slight resurgence to category 2, Lala resumed weakening as it encountered steadily cooler waters in the subtropics. It did not accelerate northeastward, though, but instead resumed a plodding northwest trajectory as another ridge blocked its exit. The storm spent another week on this general path, diminishing to a tropical storm on August 22 and finally to a post-tropical storm on August 27, just east of the International Dateline, having reached a latitude over 38°N.
Lala spent 14.5 days as a tropical cyclone, all in the Central Pacific. This surpassed the previous Central Pacific record of Hurricane Ana of 2014, which had lasted 12.75 days. Notably, the storm took a jog near the islands: it approached on a west-northwest path, turned a little left and avoided a Big Island landfall, and then curved back to the right after passing the Big Island before resuming a westward course. This is actually a well-studied phenomenon; data indicate that the high topography of the Big Island influences the track of approaching storms, deflecting them in a curve around land.
Still, such events are not so common. The image above shows tropical cyclones of tropical storm strength or above that have passed within 50 miles of Hawaii in the period 1949-2026. Lala is the closest hurricane approach to the Big Island in the official record, though historical accounts suggest a significant hurricane may have made landfall there in 1871. The category 4 landfall of Hurricane Iniki in Kauai on September 11, 1992 remains the strongest ever recorded in the state.
Regardless of the specifics of how close Lala came to landfall, its effects were widespread. The map above shows the total rainfall map over the duration of the storm. As always in Hawaii's climate, the mountains had a huge impact: east-facing mountainsides and coastlines faced the oncoming winds as the counterclockwise rotation of Lala brought rainbands into the islands from the sea. These areas received extreme rain totals, in contrast to smaller amounts in the leeward areas. The greatest total was 43.54 inches of rain (1106 mm) at Laupāhoehoe, a point in the northeast corner of the Big Island. This was the third-largest rainfall total ever recorded in the state of Hawaii from a tropical cyclone. These rains caused widespread flooding. Footage from the summit of Mauna Kea also recorded snowfall as the storm passed, a very rare effect for a hurricane. Widespread tropical storm force winds also occurred across the islands, with peak gusts on the Big Island, Maui, and Oahu reaching hurricane strength. These winds knocked out power for hundreds of thousands of people. The highest recorded gust, again at the Mauna Kea summit, was a remarkable 140 mph (225 km/hr).
Hawaii continues to recover from Lala's passage. There were 3 known direct fatalities from the hurricane. The storm's approach was well-predicted, however, with a close pass anticipated before Lala was even named. These improvements in forecasting are essential to hurricane safety preparations.
The continuing El Niño event will likely bring other tropical cyclones to the region near Hawaii in the coming year. For now, Lala is the latest chapter in the not-so-well-known story of Central Pacific hurricanes.
Sources:
- https://community.wmo.int/site/knowledge-hub/programmes-and-initiatives/tropical-cyclone-programme-tcp/tropical-cyclone-regional-bodies,
- https://www.nhc.noaa.gov/aboutcphc.php, https://www.hawaiinewsnow.com/2026/08/23/lala-moke-how-hawaiis-tropical-storms-get-their-unique-names/,
- https://www.nytimes.com/2026/08/15/weather/tropical-storm-lala-name-hawaii-hurricane.html,
- https://yaleclimateconnections.org/2026/08/hawaii-reeling-after-lalas-powerful-sideswipe/
- "North-Central Pacific Tropical Cyclones: Impacts of El Nin˜o–Southern Oscillation and the Madden–Julian Oscillation" by Klotzbach and Blake, 2013
- "The Effect of Hawai’i’s Big Island on Track and Structure of Tropical Cyclones Passing to the South and West" by Chambers and Li, 2011
No comments:
Post a Comment