The NOAA Hurricane Cone Explained — Florida

The National Hurricane Center (NHC) Tropical Cyclone Forecast Cone — widely called the cone of uncertainty — is the most recognized hurricane graphic in the United States. Issued with every NHC tropical cyclone advisory, it depicts the probable path of a storm's center over the following five days. The NHC, headquartered at 11691 SW 17th Street in Miami, Florida, operates under NOAA's National Weather Service and publishes updated cone graphics every six hours throughout the lifespan of a named system, or more frequently during special advisories.

Before the cone existed, NHC advisories plotted the forecast track as a single line connecting predicted eye-center locations — a format that researchers and former NHC officials have described as the skinny black line. Track forecasts originally extended three days; in 2003 the NHC extended them to five days, according to Yale Climate Connections. The cone first appeared in 2002, introduced specifically to shift public attention from a single pinpoint landfall prediction toward the range of probable paths. Florida, with its peninsular shape, extensive coastline, and position at the geographic center of Atlantic hurricane risk, is the state most frequently placed within an active cone.

The NHC defines the cone with mathematical precision. At each forecast interval — 12, 24, 36, 48, 72, 96, and 120 hours — the NHC anchors a circle whose radius is set so that two-thirds (67 percent) of historical NHC absolute track errors over the previous five-year sample fall within that circle. The cone's outline is the area swept out by those circles across the full forecast period. The operational circle-based methodology has been in use since 2007; for the 2026 hurricane season, the NHC published updated circle radii derived from error statistics covering 2021 through 2025, as documented on the NHC cone definition page.

The graphic itself is divided into two zones. The solid white area covers the first three days of the forecast; a stippled region extends from days four through five to reflect the greater uncertainty at longer ranges. Historical data show that the entire five-day path of a storm's center remains within the cone approximately 60 to 70 percent of the time, meaning that on average, 30 to 40 percent of actual storm tracks fall outside the cone's boundaries, according to the NHC forecast cone documentation. Because uncertainty compounds over time, the cone grows wider as the forecast period extends. Even with the overall accuracy improvements in NHC track forecasting, five-day track forecasts still carry average errors of approximately 200 miles, according to News4JAX.

The NHC publishes the cone graphic both with and without a central forecast track line and provides an option for users to remove the central line from the hurricanes.gov display. Former NHC Director Max Mayfield has been quoted on the tension this creates: the central line is useful to forecasters who understand its probabilistic context, but it reinforces point-forecast thinking for general audiences who may treat it as a precise trajectory.

The NHC explicitly states that the cone does not represent the size of the storm, the extent of damaging winds, the storm's intensity, or the geographic area that will experience impacts. Dangerous conditions — including tropical storm-force winds, hurricane-force winds, storm surge, tornadoes, and flooding — routinely occur well outside the cone's boundaries. A storm nearly 500 miles wide, such as Hurricane Ian, can produce destructive conditions across areas that never appear inside the cone at any advisory cycle.

A study published in the Bulletin of the American Meteorological Society in August 2022 and reported by the Association of Certified Meteorologists surveyed more than 2,800 Florida residents and found that almost half believed the NHC forecast cone represented the spatial extent of the storm itself — a documented misreading with direct safety implications. The same analysis noted an in-or-out thinking problem: residents inside the cone's boundary may assume they face the full storm threat, while those just outside may dismiss the hazard entirely, even though the cone only describes where the storm's center is likely to travel.

To address the wind hazard gap, the NHC issues a separate Wind Speed Probabilities product each advisory cycle. Published in both tabular and graphical form, the product provides the probability of experiencing 34-knot (tropical storm force), 50-knot, and 64-knot (hurricane force) winds at specific locations — capturing the reality that destructive winds extend far beyond the storm center's probable path. Florida's 67 county emergency managers, the Florida Division of Emergency Management, and local National Weather Service forecast offices use this product alongside surge inundation maps and local evacuation zone maps when formulating public guidance.

Hurricane Ian's September 2022 landfall crystallized years of documented concern about cone misinterpretation. At 5 p.m. on September 23, 2022, the NHC issued a cone graphic showing Ian's track nearly five days before landfall, according to Yale Climate Connections. As Ian approached, the NHC shifted the forecast track southward from the Tampa Bay area toward Sarasota County — a relatively small adjustment in terms of track error, but one with large consequences for which communities faced the most severe storm surge.

Fort Myers remained on or near the edge of the cone throughout all advisory cycles before Ian's September 28, 2022 landfall, as documented by the Association of Certified Meteorologists. Lee County officials cited track uncertainty in delaying mandatory evacuation orders until September 27, 2022 — one day before landfall and more than a day after the NHC had issued storm surge watches for the county's coastline, according to NPR. At least 119 people died in Florida from Ian, with most deaths attributed to storm surge drowning in Lee County; Fort Myers Beach and Sanibel were among the hardest-hit areas.

WGCU News reported that meteorologist James Franklin noted a small track error can translate into a large change in which coastal communities face the most dangerous conditions. The case also illustrated the cone's shrinking characteristic: as a storm approaches, the cone narrows — a feature that can give the misleading impression of increasing certainty about precise impacts just when a wide storm's full destructive reach is still expanding. Cedar Key, which also appeared within Ian's cone in some advisory cycles, experienced minimal impacts, while communities on the cone's southern edge sustained catastrophic damage.

No region of Florida is inherently exempt from appearing within an active tropical cyclone cone. The state's peninsular shape means that storm tracks crossing from the Gulf of Mexico to the Atlantic, or vice versa, place interior counties inside a cone even when those counties are far from the coastline. Central Florida and North Florida can experience tropical storm-force winds and flooding while technically at or beyond the cone's edge, as recurring post-storm damage records document.

Florida's Gulf Coast — particularly the southwest coast from the Florida Keys northward through the Tampa Bay area — and the Southeast Atlantic coast from Miami through Palm Beach County and the Treasure Coast are historically the most frequent recipients of active cone coverage, reflecting the dominant tracks of Atlantic basin tropical systems. The Florida Panhandle has also been placed within major cones during significant landfalls, including Hurricane Michael's October 2018 Category 5 strike near Mexico Beach.

The operational consequence differs by region. Coastal counties face compounded storm surge risk that the cone does not visually represent; the NHC issues storm surge watches and warnings as companion products specifically to fill that communication gap. Inland counties must contend with freshwater flooding and wind damage from systems that may have weakened after crossing the coast — hazards that the cone's track-centered design does not foreground. The NHC's 2025 storm surge watch for the entire west coast of Florida issued before Ian illustrated how broadly surge risk can extend even when the cone's track appears to point at a specific coastal segment.

For the 2026 hurricane season, the NHC announced an experimental redesign of the cone graphic. The new version replaces the circles anchored at each forecast point with ellipses that separately account for along-track (speed) error and cross-track (directional) error components — a methodological shift from the circle-based approach that has been operational since 2007. The NHC is soliciting public comment on the experimental version through November 30, 2026, via a survey hosted through the National Weather Service.

In 2024, the NHC introduced an experimental addition of inland tropical storm and hurricane watch and warning depictions directly onto the cone graphic, as described in the NHC Cone Graphic Change Announcement. This addition was intended specifically to convey that wind hazards extend well inland and are not confined to the coastal zone shown most prominently in traditional cone imagery. The 2024 change represented a direct response to documented public misconceptions about storm extent — the same class of misreading that the post-Ian research community had highlighted.

Both changes reflect ongoing national debate about weather-graphic design and its behavioral effects on public evacuation decision-making, a debate that Florida's experience with Ian brought into sharp institutional focus beginning in late 2022.

Florida Statutes Chapter 252 defines county emergency management authority, including the power to issue evacuation orders. Those orders are informed in part by NHC cone and surge products, which means that the graphic's interpretation by county officials has direct legal and operational consequences for Florida's approximately 22 million residents. The Florida Division of Emergency Management coordinates with the NHC and local National Weather Service forecast offices to translate cone graphics, wind probability products, and surge inundation maps into actionable county-level guidance.

The cone connects to Florida's storm surge communication infrastructure: the NHC's surge watches and warnings, issued as companion products to the cone, are designed to communicate water hazard extent that the cone itself cannot convey. Following Hurricane Andrew in 1992, Hurricane Charley in 2004, and Hurricane Michael in 2018, each generation of post-storm analysis has informed changes to how the NHC presents and labels its graphics — a feedback loop between Florida's storm history and national forecast communication standards.

NOAA's Hurricane Forecast Improvement Program and the NOAA Hurricane Research Division, which maintain research partnerships with Florida universities, have driven the track forecast accuracy improvements that underlie the cone's circle radii. Improved track accuracy narrows the cone and, in principle, reduces the geographic area of public uncertainty — but as Ian demonstrated, a narrower cone can paradoxically reinforce overconfidence about which specific communities face the greatest risk when a large storm's wind and surge fields remain far broader than the cone implies.