Residents of Hawaii and crews navigating transpacific shipping lanes face a 2026 hurricane season that NOAA expects to run well above average. The agency’s Central Pacific Hurricane Center forecasts between 5 and 13 tropical cyclones in the basin stretching from 140 degrees west longitude to the International Date Line during the June 1 through November 30 season. The upper bound of that range would nearly triple the 1991-2020 climatological average of 4.4 systems, placing the region on watch for one of its most active periods in the modern record.
Why a 5-to-13 cyclone range signals elevated risk for Hawaii
The gap between the forecast floor and the long-term average tells the story. NOAA’s Climate Prediction Center sets the near-normal band for Central Pacific tropical cyclone activity at just 4 to 5 systems per season. Even the low end of the 2026 outlook matches that threshold, while the high end more than doubles it. A 70 percent probability is assigned to the 5-to-13 combined count of tropical depressions, tropical storms, and hurricanes. For island communities where a single close-passing storm can trigger flooding, power outages, and port closures, a season skewed this far above the baseline changes the calculus for emergency planners and insurers alike.
The forecast leans heavily on the probability of El Niño conditions developing or persisting through the summer and fall. El Niño events historically shift the zone of active cyclone formation eastward, pulling more storms into the Central Pacific basin that might otherwise spin up farther west. NOAA now tracks those ocean-atmosphere signals through a retooled metric called the Relative Oceanic Niño Index, or RONI, which the Climate Prediction Center adopted for ENSO monitoring to improve responsiveness and reliability. RONI is defined as the three-month running mean of ERSST.v5 Niño 3.4 sea surface temperature anomalies adjusted by tropical-mean anomalies, a refinement designed to filter out background warming that can distort older indices.
Whether RONI actually sharpens seasonal outlooks is a question that will take several years of verification data to answer. If the new index narrows the error range for Central Pacific cyclone counts compared with pre-RONI forecasts, that improvement should show up in standard verification statistics within roughly three hurricane seasons. Until those comparisons exist, the practical value of the switch remains an informed bet by CPC scientists rather than a proven upgrade.
NOAA’s forecast data and the ENSO signal driving the numbers
The 2026 Central Pacific outlook draws its numbers from ENSO strength probabilities issued by the Climate Prediction Center and from historical relationships between El Niño phases and basin-level storm counts. The 1991-2020 average of 4.4 tropical cyclones serves as the statistical baseline. In seasons when moderate-to-strong El Niño conditions have been present, Central Pacific activity has routinely exceeded that average, sometimes by a wide margin.
CPC’s June 2026 ENSO strength tables feed directly into the seasonal hurricane models. Those tables break down the likelihood of neutral, weak, moderate, and strong El Niño or La Niña conditions across overlapping three-month windows. When the probability mass shifts toward El Niño, forecasters widen and raise the cyclone count range for the Central Pacific while often trimming expectations for the western Pacific, where El Niño tends to suppress formation.
The basin-wide forecast also incorporates analog seasons-past years with similar ocean temperatures and atmospheric patterns-to estimate how many disturbances are likely to develop into named storms or hurricanes. In El Niño analogs, warmer waters and reduced vertical wind shear near and east of Hawaii have historically favored more frequent and sometimes stronger systems. That statistical relationship underpins the higher-end scenario of a dozen or more cyclones entering or forming within the Central Pacific this year.
For anyone living in or traveling through the Hawaiian Islands between now and late November, the practical takeaway is straightforward. Even a near-normal season can deliver heavy rainfall, dangerous surf, and disrupted flights. A season at or near the top of the forecast range raises those odds sharply. Households should confirm insurance coverage, review evacuation routes, and stock basic supplies before the peak months of August and September, when Central Pacific activity historically concentrates.
Gaps in the outlook and what to watch next
The 2026 forecast provides a basin-wide count range but stops short of projecting individual storm tracks or landfall probabilities for specific islands. No public-facing NOAA product currently breaks the 5-to-13 range into separate bins for tropical depressions, named storms, and hurricanes within the Central Pacific alone. That limits how precisely local officials can translate the seasonal outlook into resource allocation decisions, such as how many shelters to open or how aggressively to stage fuel and medical supplies on neighbor islands.
Equally absent from the public record so far is any detailed response from Hawaii state emergency management agencies describing how the above-normal forecast will shape staffing, shelter pre-positioning, or budget requests. Without that information, it is difficult to gauge whether the state’s preparedness apparatus is scaling to match the elevated risk NOAA has identified. County-level planning documents for Honolulu, Maui, Kauai, and Hawaii counties have not yet been updated with season-specific annexes tied to the 2026 outlook, leaving residents to rely on generic hurricane guidance.
Another limitation is the lack of clarity on how climate change may be interacting with ENSO-driven patterns in the Central Pacific. While global studies have examined potential trends in storm intensity and rainfall, NOAA’s current seasonal products focus on counts rather than on how strong or wet individual cyclones might become. That emphasis on frequency over intensity leaves open questions about whether a smaller number of storms could still deliver outsized impacts if they arrive with higher peak winds or extreme precipitation rates.
The next development to track is the mid-season update that the Climate Prediction Center typically issues in August, when additional months of observed sea surface temperatures, wind patterns, and early-season storm behavior can refine the ENSO outlook. If El Niño conditions strengthen more than expected, the upper bound of the cyclone range could gain credibility, and messaging to coastal communities may shift toward more urgent preparedness. Conversely, if the ocean cools back toward neutral, forecasters could trim the high end of the range, though even that scenario would still leave Hawaii facing at least a near-normal season.
Between now and that update, residents and maritime operators will have to navigate a forecast that is statistically robust but operationally blunt. The 5-to-13 range signals a clear elevation in risk without specifying where or when the most dangerous storms might strike. In practice, that means treating the entire June-to-November window as a period of heightened vigilance, with particular attention to weekly outlooks and individual storm advisories as they are issued.
For Hawaii, where the margin for error is narrow and supply chains are long, the 2026 hurricane season will test how well long-range climate signals can be translated into concrete action on the ground. NOAA’s outlook and ENSO diagnostics provide an early warning that the dice are loaded toward a busier-than-usual year. What remains to be seen is how effectively state and local agencies, businesses, and households respond to that warning before the strongest storms of the season form on the Central Pacific horizon.
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*This article was researched with the help of AI, with human editors creating the final content.
